Two-time champion Rafael Nadal marked his return to Centre Court with a 6-4 6-2 7-5 victory over Donald Young to reach the third round at Wimbledon.

The 31-year-old Spaniard, who missed last year's tournament through injury, looked to be easing to victory until he was broken by the aggressive American when serving for the match.
But the world number two broke back and served out to love to seal the win.
Fourth seed Nadal will face Russia's 30th seed Karen Khachanov on Friday.
He joins potential semi-final opponent Andy Murray in round three after the world number one beat Dustin Brown in straight sets.
Fellow top-four seeded players Roger Federer and Novak Djokovic play their second-round matches on Thursday.
"I played a solid match and served well until the break," Nadal told BBC Sport. "It's great to be in the third round without losing a set.
"I'm just trying to go day by day. I'm taking it easy, trying to enjoy every moment. This tournament is so special."
After winning easily in Monday's first-round tie against John Millman on Court One, this was Nadal's first match back on Centre Court since a shock defeat by Dustin Brown in 2015 - he missed last year's championships with a wrist injury.
That loss to Brown capped a miserable run of four straight losses to players ranked 100 or lower at the tournament he won in 2008 and 2010.
However, at times against Young, especially in the second set, Nadal looked back to his imperious best, continuing the form that saw him finish runner-up at the Australian Open and claim his 10th French Open title this season.
The 15-time Grand Slam champion hit 37 winners in total - many of those with his imposing forehand - and won 80% of points on his first serve.
Young hit 31 winners himself, the world number 43 providing a stern test and plenty of entertainment for the crowd, particularly when he halted Nadal's progress in the third set.
Yet Nadal prevailed. He may have come into the tournament with questions over his current abilities on grass - Monday's match was his first on the surface in two years - but this showing suggested he could be ready to emulate past successes at Wimbledon.
Three-time Wimbledon champion Boris Becker
We all wanted to see how Nadal played on grass - he hadn't showed up in a while. But from what I've seen so far, he looks strong, he looks confident, he looks hungry.
He is the ultimate competitor and will give all he has got. Of course, everybody's favourite is Federer but then you have Murray and Djokovic.
The big four are back. They all have a realistic chance, but it depends who they go up against.
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Elsewhere on Wednesday, there were few upsets in this half of the men's draw, which contains Nadal and Murray.
Two-time semi-finalist Jo-Wilfried Tsonga needed less than two hours to beat Italy's Simone Bolelli 6-1 7-5 6-2 - although the French 12th seed was troubled by the swarm of flying ants that descended on Wimbledon.
"I've had a few experiences in the United States, with the light at night sometimes you have big bugs," said Tsonga.
"But this was a little bit different, because these ones was very small but a lot, so it was special sometimes, it was in my nose and in my ear."
Tsonga faces American Sam Querrey in the third round after the 24th seed saw off Georgia's Nikoloz Basilashvili 6-4 4-6 6-3 6-3.
Croatia's seventh seed Marin Cilic eased past Germany's Florian Mayer 7-6 (7-2) 6-4 7-5 to set up a tie against American 26th seed Steve Johnson.
Despite a laboured performance, ninth seed Kei Nishikori came through 6-4 6-7 (7-9) 6-1 7-6 (8-6) against Ukraine's Sergiy Stakhovsky and will meet Spain's 18th seed Roberto Bautista Agut next.
However, 14th seed Lucas Pouille of France is out, beaten by 2013 semi-finalist Jerzy Janowicz, with the Pole sealing a 7-6 (7-4) 7-6 (7-5) 3-6 6-1 win.


Anti-fracking campaigners are considering a possible legal challenge after plans to begin the controversial technique were approved by councillors.

North Yorkshire County Council voted 7-4 in favour of Third Energy's application to extract shale gas at a site near Kirby Misperton in Ryedale.
Friends of the Earth and Frack Free Ryedale said they would be seeking legal advice and launched a People's Declaration in a bid to stop fracking.
Third Energy says the process is safe.
Fracking is the process of drilling down into the earth before a high-pressure water mixture is directed at rock to release the gas inside.
Opponents say it can cause water contamination, earthquakes and noise and traffic pollution.
Third Energy's application was passed by the council's planning committee on Monday.
More than 4,300 objections to the application were received and 100 people gave evidence during the two-day hearing. Just 36 representations in support of the application were received.
Ryedale District Councillor Di Keal, of Frack Free Ryedale, told BBC Radio York: "People are very down, people are very upset - there were tears yesterday. But I know people round here, they will stand up and they will fight. This battle does go on.
"We will be looking to take legal opinion on what we can do."
Friends Of The Earth campaigner Simon Bowens said the organisation would "consider all options available, and that includes judicial review", but would not expand on what any legal challenge might focus on.
Both groups are urging people to support their campaign by signing a Public Declaration, which states that "we remain opposed to fracking in Yorkshire, in Britain, and across the world".
Protesters have also raised concerns that passing the application will open the floodgates to hundreds of other wells.
But planning committee chairman Peter Sowray said: "This planning application has nothing to do with any more wells. It was just about the test stimulation of the one well."
He said some opposition was based on "emotions" rather than "genuine planning reasons", and he was confident in the safety assurances given by Third Energy and the Environment Agency.
Since the application was passed, Conservative councillor Cliff Trotter, who voted in favour of fracking, said he had received intimidating emails.
He told BBC Radio 5 Live: "Yes, a few. But that's par for the course, I suppose."
Third Energy operations director John Dewar said he was "absolutely confident" that the operation - called KM8 - would run according to plan. He could not say whether fracking there would be commercially viable.
"What we can't predict at this moment in time how much [gas] will flow and how long it will flow for," he said.
"We do know the gas is down there and I'm absolutely confident we will be able to fracture each of the five zones safely, and then we just have to wait and see what quantity and what rate of gas comes back."
The onshore energy industry has welcomed the decision.
The chief executive of UK Onshore Oil and Gas, Ken Cronin, said fracking could help to combat climate change.
He said: "What we've seen in the US is a massive reduction in emissions coming from the electricity sector, as a result of a shift from coal to gas.
"We've also seen a very significant shift from coal to gas in this country over the course of the last six months.
"And that's partly down to the North Sea, partly down to on-shore and also partly down to renewables."


With some of the biggest names in music gathering in one studio to record a track, you might think there would be one or two "egos" in the room.

But Sam Smith said that was not the case for charity single Band Aid 30, and everyone was "pretty chilled out".
"There's a really good spirit in there actually," he said, speaking to Newsbeat at the recording in London.
"There's not a lot of ego. Everyone's pretty chilled and just looking to do a good job for the cause."
One Direction, Emeli Sande, Rita Ora and Ed Sheeran are among some of the names set to appear on the song, which aims to raise money to help the Ebola crisis in West Africa.
"I'm very excited to do something for the cause and that's the main thing for me," said Smith.
"I really want to draw the focus in on that, that's what I'm excited about the most."
Ellie Goulding, Sam Smith, Chris Martin and Bono are also singing on the track, an updated version of Do They Know It's Christmas?
"I'm actually a bit nervous because the song might be in a really bad key but again it's not about how my voice sounds in terms of whether it's suitable for me," said Smith, before recording his part.
Many of the stars dropped other commitments in order to be a part of the fundraising.
Rita Ora was the first to record her lines and left early so she could travel to Salford to film BBC One's The Voice.
Ed Sheeran flew in from his tour in Germany, while Bastille cancelled two US arena gigs to be involved.
Other artists taking part include Elbow, Seal, Jessie Ware, Fuse ODG, Sinead O'Connor, Angelique Kidjo, Olly Murs, Paloma Faith, Queen drummer Roger Taylor, Clean Bandit and Foals.
Nick Grimshaw was also at the studio, to "help" with the recording.
"I really want to sing, like so much, but I've definitely been told I can't because my voice is awful," he said.
"But I keep saying to Bob [Geldof], surely it's a choir and I can just sneak in at the back."
Bob Geldof, who is behind the appeal and organised the original track in 1984, said he addressed the participants "like the headmaster" before they sang the chorus.
"I said, 'OK, this is what it's about. When you sing this, be aware that the rest of the world will be singing it with you.'
"I explained the situation in West Africa, I explained what the UN were saying, explained what we could do, and just geed them up."
Many of the musicians involved were children when the first Band Aid single was released 30 years ago - and some weren't even born.
"I grew up watching the two Band Aids that happened and watching Live Aid and all of that was incredible," said Smith, who is 22.
"This is all amazing but a day like today just highlights what it's really about if I'm honest."
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An all-girl team of roboticists from Afghanistan will watch their creations compete in a US competition via Skype after being denied entry visas.

President Trump recently ordered a ban on travel from six Muslim-majority countries, but Afghanistan was not included on the list.
Teams from Iran, Sudan and Syria - which are on the list - did manage to enter the country.
The girls said they did not know why they had not been given visas.
A US State Department official said it could not discuss individual cases. A team from The Gambia also failed to gain visas.
The six-member team will watch their ball-sorting robot compete in Washington DC via a video link from their hometown of Herat, in western Afghanistan.
"We still don't know the reason why we were not granted visas, because other countries participating in the competition have been given visas," Fatemah Qaderyan, 14, told Reuters.
She was one of the team members who made two journeys to the US embassy in the Afghan capital, Kabul, to apply for their papers.
Team-mate Lida Azizi, 17, said: "All of the countries can participate in the competitions, but we can't. So it's a clear insult for the people of Afghanistan."
The First Global competition has seen teams from 164 countries compete in a series of robotic games.
The non-profit organisation aims to promote Stem subjects (science, technology, engineering and maths).
First Global's president, Joe Sestak, said in a post on the organisation's Facebook page that he was "saddened" by the US decision, adding his own thoughts as to why the girls had been refused visas.
"Visa decisions are often made regarding many whose lives are endangered," he wrote. "This is compounded by the low number of visas available within the nation to begin with."
A group of Afghan girls based in the US will represent the team, and the Skype call will be broadcast on a big screen at the event.


Al Ahly chairman Mahmoud Taher is backing Hossam Ghaly to return to play for Egypt, now that a row the player had with a national team assistant coach has been resolved.

Ghaly is not in Egypt coach Hector Cuper's squad for June's Africa Cup of Nations qualifier against Tanzania.
The omission of the Ahly captain follows reports of an argument with assistant coach Osama Nabeh in March.
"The problem between Osama Nabeh and Hossam Ghaly has ended," Taher said.
"I held a meeting with Hany Abo Rida - the general supervisor of the Egyptian National team - and we resolved things.
"The meeting was meant to include Ghaly and Nabeh but the player is preparing for a league match on Wednesday.
"Ghaly is one of the most important players in Egypt now and I'm sure he will back in the national team soon."
The 34-year-old, who played for Tottenham Hotspur in England and also had spells in Belgium and Netherlands, has played more than 70 times for Egypt.
The Pharaohs will face Tanzania in Dar es Salaam on 4 June needing just a draw to seal qualification for next year's Nations Cup finals in Gabon.
Cuper has recalled Zamalek's Mohamed Ibrahim and Al Ahly duo Ahmed Fathy and Hossam Ashour.
The Pharaohs are due to begin their training camp on Thursday and were due to play a friendly against DR Congo on 29 May, but that game has since been cancelled.
Egypt Squad:
Goalkeepers: Essam El-Hadary (Wadi Degla), Sherif Ekrami (Al Ahly), Ahmed El-Shennawy (Zamalek)
Defenders: Ahmed Fathy (Al Ahly), Mohamed Abdel-Shafy (Al Ahly Saudi, Saudi Arabia), Hazem Emam (Zamalek), Ahmed Hegazy (Al Ahly), Rami Rabia (Al Ahly), Sabry Rahil (Al Ahly), Ali Gabr (Zamalek), Ayman Ashraf (Smouha), Hamada Tolba (Zamalek), Karim Hafez (AC Omonia, Cyprus)
Midfielders: Abdullah El-Said (Al Ahly), Hossam Ashour (Al Ahly), Mohamed Elneny (Arsenal, England), Mohamed Salah (Roma, Italy), Mohamed Ibrahim (Zamalek), Tarek Hamed (Zamalek), Mohamed 'Trezeguet' Hassan (Anderlecht, Belgium), Moemen Zakareya (Al Ahly) and Amr Warda (Panetolikos, Greece)
Strikers: Marwan Mohsen (Ismaily), Ahmed 'Koka' Hassan (Sporting Braga, Portugla), Amr Gamal (Al Ahly)


A woman, believed to be in her 80s, has died following a blaze at a house in the village of Lhanbryde near Elgin in Moray.

Fire crews were called to a property on Robertson Road just before 07:30.
The Scottish Fire and Rescue Service said crews had used breathing apparatus as they tackled the fire.
Senior officer for Moray and Aberdeenshire, David Rout, said: "Our thoughts are with the family. We will now investigate the cause."


Jump racing's former champion chaser Sprinter Sacre is to miss Saturday's Tingle Creek Chase at Sandown, says his trainer Nicky Henderson.

The nine-year-old, who has been treated for a heart condition, won for the first time since April 2013 in this month's Shloer Chase at Cheltenham.
He is now likely to race the Desert Orchid Chase at Kempton on 27 December.
"He just doesn't need another race at the moment and it's as simple as that," said Henderson.
"With Sprinter, the Desert Orchid at Kempton is the likely place for him and if he needs another run before Cheltenham, fine.
"We don't need to run him again. We're not going to learn anything. But he looks fantastic - he looked great coming into the race and he looks fantastic coming out of it."


Wrexham beat Welling to move within touching distance of the National League play-offs.

Lee Fowler's close-range finish and a penalty from Connor Jennings gave Wrexham a commanding 2-0 half-time advantage.
Kayden Jackson hit the post as Wrexham continued to press after the break but were unable to add to their lead.
Wrexham are now sixth in the table and only behind Gateshead, in the final play-off spot, by two points.
Manager Gary Mills told BBC Radio Wales: "We've played well today and in the second half I thought we were outsanding.
"It was an excellent performance. It's never easy coming here, we know that, and I think it's the first time I've won here actually and it feels good."


Everton survived a major League Cup scare at Barnsley with two goals in extra time goal sending them through.

The hosts raced into a 2-0 lead through Sam Winnall and Marley Watkins but Everton responded with an acrobatic Kevin Mirallas strike and a Steven Naismith header.
Daniel Crowley drove the Tykes back in front but Romelu Lukaku swept home to send the match to extra time.
Marc Roberts put through his net before Lukaku ended the thrilling cup tie.
Conor Hourihane had rattled the bar with a curling shot in the second period of extra time, but the League One side's fatigue told as Everton wrapped up the victory.
But they were pushed all the way by an adventurous Barnsley side who forced the Premier League side into errors and posed a constant threat going forward.
The Toffees - for whom Chelsea target John Stones played the full 120 minutes against his former club - will now travel to Reading in the third round.
Everton made a statement by including Stones in their line-up.
The 21-year-old England defender has handed in a transfer request to try and force through a move to Chelsea, who have had a third offer of £30m turned down.
It was a clear signal that, for now, he is part of Everton's plans - but the stresses of his situation appeared to show on the youngster who has been outstanding so far this season.
Stones, back at his first club, was not his usual composed self and made an error of judgement when Winnall gave the home side the lead, inexplicably stepping over his goalbound shot.
The defender received a mixed reception from Everton's fans but he, and Roberto Martinez's side, came through unscathed - and now he must wait to see what the next move on his future will be before Tuesday's transfer deadline.
Everton manager Roberto Martinez has made the Capital One Cup a priority this season as this is the competition that has got away from the club over the years.
And he played a relatively strong side, with Lukaku up front and Stones and Phil Jagielka forming an established central defensive partnership.
There were still risks with some changes and it was reflected in the fact he needed to bring on Gerard Deulofeu and Ross Barkley to rescue a 2-0 deficit at half-time.
The inclusion of Aiden McGeady was mystifying, as proved by the young Spaniard's sensational game-changing display.


Hearts aim to build a new 7,000-seat main stand at Tynecastle, which will increase the stadium capacity to over 20,000.

The Scottish Premiership club announced their intention to redevelop the ground in December.
And now they have submitted a pre-application notice to Edinburgh City Council before an eight-week public consultation process.
The plans include space for a club shop and ticket office.
The current main stand has 4720 seats and has changed little since it was built in 1914, with some views obstructed by pillars.
The three other stands at Tynecastle were constructed between 1994 and 1997.


Two men have been arrested following the disappearance of a 15-year-old girl in Leicestershire.

Kayleigh Haywood has not been seen since she was dropped off at Ibstock Community College on Friday.
The teenager made contact with her parents on Saturday morning but has not been heard from since.
Two men, aged 27 and 28, have been arrested in connection with her disappearance and are currently in police custody.
Updates on this and other stories on Leicestershire Live
An alleyway off Usborne Way in Ibstock has been cordoned off, which police said is connected with Kayleigh's disappearance but officers would not reveal more.
Police activity has centred around Baker's Croft estate near Ibstock and also around the Sence Valley Forest Park.
The two men were arrested in the Coalville and Ibstock areas of the county.
Kayleigh, from Measham, is described as being a "bright, intelligent and popular girl" who is about 5ft 6in (1.7m) tall, medium build, with mousey coloured long hair.
She had planned on a night away from home on Friday and on Saturday morning telephoned her parents but has not made contact since.
Det Ch Supt David Sandall said: "We don't know where she is and this is totally out of character for her.
"We have a dedicated team of officers carrying out enquiries to try and locate Kayleigh.
"It is now more than three days since she was last seen by her family and they, and us, are becoming increasingly concerned about her safety."


Drivers are to be charged a fee of £2 to drop off passengers at Glasgow Airport in future.

The charge is expected to take affect from the end of April when a new pick-up and drop-off point will open opposite the main terminal building.
A spokeswoman said the charge was being introduced after "all possible alternatives" to ease congestion at the airport had been exhausted.
A pick-up fee has been in place at the airport since 2010.
Construction work is currently under way to create the new pick-up and drop-off zone, where the £2 charge will entitle drivers to a 10-minute stay. Blue badge holders will be exempt.
The work will also see the traffic flow on St Andrew's Drive, where the Holiday Inn Express is located, reversed. This change is due to take affect in March.
Amanda McMillan, managing director of the airport, said the investment represented one of the most significant upgrades to the road network in more than 10 years.
She added: "It has been apparent for some time that our current drop-off area, which suffers from severe congestion on a daily basis, is simply no longer fit for purpose.
"It was implemented at a time when we were carrying 6.5 million passengers, however, we have since enjoyed sustained growth and are now fast approaching the 10 million mark."
Ms McMillan acknowledged that the new arrangement would be unpopular.
She added: "We have resisted introducing a drop-off charge despite most airports of our size having similar arrangements in place for many years, however, having exhausted all possible alternatives we have now reached a point whereby a chargeable facility is the only way to address congestion, discourage non-airport traffic and encourage best use of our road network."
Drivers will still be able to drop off people at the airport's long stay car park, which is a five-minute bus ride from the terminal building, free of charge.


A man in his 20s has been seriously injured in a car crash on Anglesey.

Police are investigating the incident, which happened at 02:15 BST on Friday on the A5025 in the centre of the village of Pentraeth.
The injured man was one of the occupants of a black Ford Mondeo which crashed.
It is understood he is local and has possible life-changing injuries.


The government's remaining 30% stake in the Royal Mail is to be sold and £3bn cut from government spending this year, George Osborne has said.

The chancellor said the Royal Mail shares money - valued at £1.5bn - would be used to pay down the national debt.
The £3bn in cuts come ahead of further reductions to be announced in July.
The NHS, schools and overseas aid are protected from cuts - but other departments such as the Home Office and MoD will have to find savings.
Labour accused Mr Osborne of "ripping up" his long term economic plan by springing the announcement on MPs.
The SNP said the move "poses real danger to the postal service and, in particular, the universal service obligation which is of huge importance to Scotland".
The government is committed to clearing the deficit by 2018/19 without increasing income tax or VAT, something Mr Osborne said would not be "easy".
He needs to find a further £30bn of savings over the next three years, including £12bn to come out of welfare spending and £13bn from cuts to government departments.
Former Labour leader Ed Miliband made his first Commons speech since losing the general election in the debate on the Queen's Speech, urging the chancellor to ensure David Cameron followed through "on his one nation rhetoric".
Mr Miliband promised to hold Mr Cameron's government to account from the backbenches and said the Labour Party needed to do some "hard and painful thinking" about why it lost the election.
The government holds a 30% stake in the Royal Mail, with the remaining 70% held by a combination of employees and private investors.
Shares in Royal Mail were initially floated at 330p per share, and were trading at 526p at market close on Wednesday but fell 2.5% on Mr Osborne's announcement.
Labour came up with the idea of selling off part of the Royal Mail, which is a separate company to the still publicly-owned Post Office, in 2008.
But the plan proved hugely controversial, with the trade unions threatening strike action and it was ditched in 2009, with then Business Secretary Lord Mandelson blaming weak market conditions.
Lib Dem Business Secretary Vince Cable resurrected the idea when the coalition government came to power.
But he was accused by the National Audit Office of selling it off far too cheaply, losing taxpayers millions. Shares climbed 70% higher than their original 2013 sale price.
Mr Cable refused to apologise, and said that the sale had raised £2bn for the taxpayer, with a further £1.5bn from the 30% stake in Royal Mail which it had retained.
Mr Osborne told MPs: "I am today announcing that the Government will begin selling the remaining 30% shareholding we have in the Royal Mail.
"It is the right thing to do for the Royal Mail, the businesses and families who depend on it - and crucially for the taxpayer.
"Further savings in departments this year - and selling our stake in the Royal Mail.
"Getting on with what we promised. Reducing the deficit - that is how you deliver lasting economic security for working people.
"For as everyone knows, when it comes to living within your means, the sooner you start the smoother the ride."
Business secretary Sajid Javid said the Royal Mail sell-off would happen "in the lifetime of this parliament" but that the government would listen to specially-appointed independent advisers about exactly how and when.
"We have plenty of time to work on this. I don't think it's the kind of thing we want to rush into in anyway."
He said his "overriding concern" was to "get the best possible deal for taxpayers".
Mr Osborne said £3bn in efficiency savings had been achieved by belt-tightening in non-protected government departments and asset sales, including publicly-owned land around King's Cross station in London.
The savings were made in the Home Office, DWP and Defra and business department including the higher and further education budgets.
The Ministry of Defence will have to find £500m of savings this year, about 1.5% of its total budget.
The MOD says that it will come from "efficiency savings" and will not impact operations or manpower. An MOD source says the cut "could have been worse" and is "manageable" but the BBC understands it might have an impact on the department's equipment plans.
Mr Osborne will set out full details of future spending cuts in a Budget statement on 8 July.
The director of the Institute for Fiscal Studies, Paul Johnson, said the £3bn worth of cuts in the current financial year was a "useful down payment" but "big difficult decisions" were still required.
"£3bn will be tough to find in a single year but it's relatively small compared with the very tough target the Chancellor has set himself," he said.
The IFS has said public spending cuts of 1% a year in 2016-17 and 2017-18 will be more difficult to achieve than was suggested in the Conservative Party's general election manifesto.
In a statement, the think tank said: "The cuts that the government announces later this year in next month's Budget and the following Spending Review may turn out to be deliverable.
"But they certainly will not feel like just 1% being taken out of each area of spending, nor will it require merely "£13 billion from departmental savings" as the Conservative manifesto described.
"While not inaccurate, these numbers give a misleading impression of what departmental spending in many areas will look like if the manifesto commitment to eliminate the deficit by 2018-19, largely through spending cuts, while not cutting spending in many areas, is to be met."
TUC General Secretary Frances O'Grady said: "The chancellor's plan for fast and extreme cuts will hold back growth, and it will slash the tax credits and vital services that workers and their families rely on."
Here is a full list of the departmental cuts announced by Mr Osborne:


The leader of September's short-lived coup in Burkina Faso has been charged with complicity in the 1987 murder of former President Thomas Sankara.

Gen Gilbert Diendere is the most senior official to be charged.
President Sankara was murdered by a group of soldiers, but the exact circumstances of his death have remained a mystery.
Mr Sankara, a left-wing radical described as "Africa's Che Guevara", is a hero for many Africans.
An autopsy found that his body was "riddled with bullets", his family's lawyer said recently.
He was succeeded by Blaise Compaore who stayed in power for 27 years, before being ousted by street protests in 2014.
Gen Diendere, who went on to be Mr Compaore's intelligence chief, was seen as a close friend and political ally of Mr Sankara at the time of his death.
He is said to have worked with both French and US intelligence agencies and helped negotiate the release of Western hostages kidnapped by jihadists groups in West Africa.
He has not commented on the charges, but his lawyers say they are preparing a response.
During Mr Compaore's rule the investigation into the murder made little progress.
Former Compaore loyalist Roch Marc Kabore was last week declared the winner of the country's first election since the long-time leader was ousted.
The transitional government, which took over after Mr Compaore was overthrown in 2014, pledged to investigate the murder.
Ten other officers have so far been charged in connection with the death of Mr Sankara.
Gen Diendere is already in detention, facing charges in connection with September's seven-day coup.


Tesco has sold its garden centre chain Dobbies for £217m as the retailer continues with its strategy of focusing on its supermarket business.

Dobbies has been sold to a group of investors led by Midlothian Capital Partners and Hattington Capital.
The sale comes a week after Tesco announced the sale of UK restaurant chain Giraffe and its Turkish business.
Tesco bought Dobbies in 2007 for £150m and it is now the UK's second largest gardening retailer.
Dobbies - which has its headquarters in Lasswade, near Edinburgh - operates 35 garden centres in Scotland, England and Northern Ireland.
Tesco said that the business contributed £17m to its annual profits last year.
Tesco has embarked on an asset sale programme in recent months, disposing of what it considers to be non-core parts of its business.
In addition to the recent sale of the Giraffe chain and Kipa, Tesco sold its South Korean business, Homeplus, last September for £4.2bn.
The sales are part of attempts by Tesco chief executive Dave Lewis to revive the retail giant's fortunes.
Announcing the sale of the garden centre business, Mr Lewis said:  "Through their hard work and dedication to customer service Dobbies colleagues have built a great business and I would like to thank them for everything they have done.
"It was a difficult decision to sell the business but we believe this agreement will give Dobbies a bright future while allowing our UK retail business to focus on its core strengths."


A court in Saudi Arabia has sentenced seven cyber activists to between five to 10 years in prison for inciting protests, mainly by using Facebook.

The men were arrested in September last year, according to Human Rights Watch (HRW), and their trial began in April.
They were charged with posting online messages to encourage protests, although they were not accused of directly taking part in demonstrations.
It is seen as the country's latest move against online political dissent.
The New York-based rights group HRW said the case was heard in an anti-terrorism court.
The longest sentence of 10 years was reportedly given to an activist who set up two Facebook groups allegedly explaining the best protest techniques.
The rights group said the men had all admitted contributing to Facebook pages supporting the leading Shia cleric Tawfiq al-Amer, who was held in February 2011 after calling for a constitutional monarchy.
His arrest provoked anti-government rallies inspired by a wave of popular revolt in the country's Eastern Region, where much of its crude oil is sourced.
The seven men were sentenced on 24 June for "allegedly inciting protests and harming public order, largely by using Facebook", HRW said.
The court also barred them from travelling for additional periods.
Several of the defendants said they had been tortured into signing confessions, according to HRW.
The case contained two elements that the Saudi authorities are particularly sensitive about, the BBC World Service's Middle East editor Sebastian Usher reports - political criticism expressed online and protests staged by the Shia minority in the east of the country.
Several Saudi human rights campaigners have recently been imprisoned. Two women were jailed earlier in June for allegedly inciting a woman against her husband, after they tried to help a Canadian who had complained of abuse by her Saudi husband.
HRW urged European Union officials to condemn the latest convictions ahead of a meeting with Gulf leaders on Sunday.
"Sending people off to years in prison for peaceful Facebook posts sends a strong message that there's no safe way to speak out in Saudi Arabia, even on online social networks," Joe Stork, HRW's deputy Middle East director, said.


The union representing Scotland's police officers has said the force can take no more operational cuts.

The chairman of the Scottish Police Federation (SPF) made the warning at the body's annual conference.
It comes after the chief constable of Police Scotland said cuts of Â£10.8m were needed over the next 12 months.
Scottish leaders from the four main political parties will be speaking at the event which marks the second anniversary of the single force.
On Tuesday, Police Scotland chief constable Sir Stephen House said savings could be achieved, but it would take "extreme measures".
SPF chairman Brian Docherty dismissed this as "fanciful nonsense".
He told the conference in South Ayrshire: "Expecting the police to do more with less is fanciful nonsense.
"All that can be delivered with less, is less."
Scottish Conservative leader Ruth Davidson addressed members of the SPF, which represents 98% of Scottish police officers.
She told the conference her party would scrap automatic early release for prisoners and supported whole-life terms for certain forms of murder, including that of police officers.
Scottish Labour leader Jim Murphy said a lack of resources for support staff meant meticulous police work was coming to nothing.
He said Labour's plans to increase taxes for those earning more than Â£150,000 a year would help raise money to tackle the problem.
First Minister Nicola Sturgeon and Scottish Liberal Democrat leader Willie Rennie were also due to speak at the event at the Trump Turnberry Resort.
The conference follows the publication of a critical report into the use of non-statutory or "consensual" stop-and-search by HM Inspectorate of Constabulary in Scotland and a second report on the issue by Police Scotland.
The Scottish government responded by setting up a new advisory group to examine the use of stop-and-search powers in Scotland.
It will present recommendations by August so that any legislation needed can be included in the Criminal Justice (Scotland) Bill.


Three men have been charged after overnight disturbances in the Holyland area of south Belfast during which police came under attack from crowds.

One officer was injured when bottles were thrown at police in Agincourt Avenue as a crowd of about 300 people gathered ahead of St Patrick's Day.
The disturbances lasted for over two hours, ending at about 04:30 GMT.
The three men, aged 19, 20 and 21, are due in court next month.  The 20-year-old was charged with assault on police.
He has also been charged with disorderly behaviour, obstructing police and resisting police.
The teenager faces a charge of riotous behaviour while the 21-year-old is charged with disorderly behaviour.
There was a heavy police presence in the Holyland on Thursday.
The PSNI said they went to the area in the early hours of Thursday after a crowd was reported to be blocking the road and throwing missiles at homes and cars.
Vehicles parked along the street were damaged during the trouble.
One police officer said some people in the crowd had been singing "pro-IRA songs".
The officer who was injured was hit on the shoulder with a bottle.
Officers were in riot gear and had police dogs.
The PSNI expressed concern that more trouble could erupt in Belfast's Holyand area on Thursday night.
Speaking on BBC's Evening Extra programme, Ch Supt Chris Noble said significant operations are ongoing in the area and that more arrests are expected.
"Where there are offences, we will be dealing with people who are committing them.
"What young people do could have a life-changing effect for them in terms of their education and their employment.
"We're dealing with people who are abusing alcohol and then abusing the community within which they live.
"I would strongly encourage people to consider the long term consequences of engaging in any anti-social or criminal behaviour. This could lead to you receiving a fine and a criminal record."
About twenty staff from Queen's University and Ulster University are spending the day and night in the Holyland area.
The BBC understands that at about 18:00 GMT, the staff were instructed by police to remain in a church in the area for their own safety.
The staff have been working with the PSNI and Belfast City Council to plan for the day for a number of months.
In 2015, a number of students from both universities were disciplined after St Patrick's Day.
Queen's University investigated 82 students, suspending five and issuing fines totalling Â£5,210.
Ulster University disciplined 84 students.
None were suspended, but a number were issued with fines of between Â£50 and Â£100.
On Thursday morning, one student living in the area said the crowd had been good-natured before the police arrived.
Another told the BBC: "It was very hectic, some would say mayhem, it was very crazy.
"There was a lot of jumping on cars, hitting cars, speeding cars, there was a couple of boys getting hit and whatever.
"But at the same time there was a lot of good craic going on."
The area has been the scene of disturbances on previous St Patrick's Days.
In a statement, Queen's University, Belfast, condemned the trouble.
It said: "Staff from the university and the students union are on the ground in the Holyland area, as they will be tonight.
"While the vast majority of Queen's students will celebrate St Patrick's Day in an enjoyable and peaceful manner, Queen's will fully investigate any complaints or reports of anti-social behaviour."
The statement said a "strict off-campus disciplinary code" is in place at the university, and that if any Queen's student is found to have brought the university into disrepute, they will be "subject to the full rigours of this code".
The university said it has been working with the PSNI, Belfast City Council, Ulster University and Belfast Met since January, and that it supports "robust enforcement of legislation in relation to anti-social behaviour".
An Ulster University spokeswoman said: "Given the significant amount of work carried out by all partners in advance of St Patrick's Day, we are disappointed with the behaviour displayed last night.
"The Holyland area of south Belfast attracts a combination of university and college students, non-residents and post-primary students, but, as yet, it is not possible to verify specifically who was responsible for last night's behaviour."
Ray Farley of the Belfast Holyland Regeneration Association described Thursday morning's trouble as disgraceful.
"It's the old expression 'when the drink gets in, the sense goes out'," he said.
"These folks, the next day when they're being disciplined or whatever's happening, they're the saddest people, but when they're with their friends they think they're invulnerable.
"They must understand that this could have serious repercussions because if you are arrested for something like this you won't be able to go to America, you won't be able to get certain jobs, you will have great difficulty.
"So I'd stress to people - please don't get yourself into the situation where you're going to drink to excess."
Briege Ruddy, from College Park Avenue Residents' Association, also condemned the disturbances.
"We will challenge this behaviour, because this is our area, residents have a right to live here, we have a right to sleep and to carry on with our work and we will do that and eventually this will change," she said.
The three men who were charged have all been released on bail and are due in court in Belfast on 13 April.


Celtic defender Erik Sviatchenko is expected to recover from a head knock when his side face Lincoln Red Imps in Wednesday's Champions League qualifier.

The 24-year-old Dane came off during Saturday's 2-1 friendly win over Wolfsburg after colliding with visiting goalkeeper Diego Benaglio.
It was a very different side to the one that lost 1-0 in Gibraltar.
Manager Brendan Rodgers said: "He's OK. He has spoiled his good looks for a few days, but he is fine."
"There was obviously a clash of heads and he's a bit swollen below the eye," he added.
Rodgers brought on 18-year-old Kristoffer Ajer to play alongside Eoghan O'Connell at the heart of the defence on Saturday.
Following an early deflected strike from Wolfsburg defender Paul Seguin, goals from Callum McGregor and substitute Ryan Christie gave Rodgers' side a win over the German Bundesliga visitors.
Midfielder Nir Bitton missed the game with a hip flexor problem.
"He was in a lot of pain yesterday," said Rodgers. "We didn't have to risk him and we will see how he is for Wednesday."
However, Rodgers insisted that he is more than covered in that area of the pitch as Stefan Johansen has shaken off an ankle complaint.
"He should be able to train on Monday," the manager said of the Norwegian. "He has had an injection in it which has settled it right down.
"The idea is he will make the first steps on Monday and we will see how he is for Wednesday.
"I don't need to worry about losing a midfield player. I think we have another 20 to pick from."


Pupils should be given lessons about the dangers of pornography, teachers say.

Pornographic images have never been more widely available, the Association of Teachers and Lecturers warns.
The ATL, meeting for its annual conference, says it is vital children do not become desensitised to graphic, sometimes aggressive, sexual imagery.
The teachers' union says staff need more guidance on how to tackle this over-sexualised youth culture.
Teachers highlighted their concern about children having access to books such as Fifty Shades of Grey.
Helen Porter, a teacher from Newbury in Berkshire, told the union's conference in Liverpool: "It is crucial that youngsters develop an understanding of sex in the media and pornography, so that they can recognise the abnormal nature of these sexual expectations and appreciate the dangers of accepting the values portrayed by the sexualised media."
Ms Porter said pornographic images led to unrealistic expectations.
"Boys who become familiar with pornography develop certain expectations of girls' bodies. Girls feel under pressure to conform to these ideals."
Seconding the conference motion to raise awareness of the problem, Berkshire teacher James Schlackman said the debate should not be regarded as "moralistic lecturing", because young people today were being exposed to "dangerously unrealistic portrayals of sex".
"Much of it [pornography] is aggressive, some of it bordering on abusive," said Mr Schlackman.
"It doesn't show normal sexual behaviour, but there is so much of it that to young people, without the benefit of experience, it appears to be normal."
Mr Schlackman said these images risked damaging children's relationships both now and in the future.
He also warned that pornography made children more vulnerable to abuse.
"Child protection experts know that a key method used to groom children for abuse is to normalise sexual behaviour to that child, to make it seem like what the abuser is asking from them is nothing unusual.
"Today, children are doing that on their own. They are routinely taking sexual photographs of themselves and sending them to others.
"They are becoming desensitised to the very activities that make them vulnerable to abuse."
One teacher told the conference she feared books like Fifty Shades of Grey normalised sexually abusive relationships.
Niamh Sweeney from Cambridgeshire argued: "It is not erotic fiction - it describes a violent and abusive relationship where a young girl admits to being hurt, not enjoying it but agreeing to it because she know he likes it."
Ms Sweeney said she had discussed the book with her lower sixth class and used it to discuss the dangers of being forced "to do something they do not want to do".
Alison Sherratt, an ATL member from Bradford raised concerns that even very young children have access to explicit images.
"It is a fact that very many of our youngest children are exposed to a wide variety of images of a pornographic nature, found even in what may be seen to be the most innocent magazines," she said.
"Little ones are seeing inappropriate films and video games while staying up late or being in the same room as other siblings.
"We are noticing a much more explicit vocabulary emerging and types of games amongst the very young that are quite sexually explicit."


A millionaire businessman whispered to a 999 operator that burglars were in his mansion, moments before he was shot through a locked door, a court heard.

Father-of-two Timothy Mardon had barricaded himself in after hearing intruders going from room to room.
Three men broke into the Grade II listed mansion in Sible Hedingham, Essex on 6 February.
One man denies attempted murder and aggravated burglary. Two others have denied aggravated burglary.
Mr Mardon, who is in his 40s, had a high-powered job at an insurance firm, but the raiders had mistakenly believed he was a drug dealer.
He told Chelmsford Crown Court he was home alone when he awoke to the sound of voices and footsteps on his gravel drive.
A man could be seen trying to force open a sash window, he said.
Mr Mardon had called 999, and was still on the line to the police when he was shot, the court was told.
A recording of the call, which lasted almost 35 minutes, was played to the jury.
"Suddenly there was a loud explosion," said Mr Mardon, giving evidence.
"I was thrown to the ground and the door burst open and the individual with the stocking over his head burst into the room wielding a gun."
The court heard the gunman screamed at him: "Where's the weed money?"
With blood pouring from the leg wound, he replied: "I don't deal weed. I work for an insurance company."
Mr Mardon said the intruder threatened to kill his family if he was lying.
Charlie Simms, 23 from Great Yeldham, Kalebh Shreeve, 24, and Christopher Bergin, 27, both from Sible Hedingham, deny charges of aggravated burglary, wounding with intent, possessing a firearm, and possessing a firearm with intent to endanger life.
Mr Simms also denies attempted murder.
The trial continues.


A 30-year-old accused of running over a man during a mass street brawl has appeared in court.

Police were called to reports of a fight on Staniforth Road in Darnall, Sheffield on Sunday evening. A man with serious injuries was found in the road.
Liam Sharp, 30, has been charged with wounding with intent to cause grievous bodily harm.
He was remanded in custody by city magistrates on Tuesday.
Mr Sharp, from Chadwick Road in Woodthorpe, Sheffield is due to appear at the city's crown court on 16 August.
South Yorkshire Police said the injured man remained in a stable condition in hospital after being found with "injuries consistent with being run over by a vehicle".
Police said a 34-year-old man arrested on suspicion of attempted murder on Monday had been bailed pending further inquiries.
Ch Insp Richard Lambert said a "potentially linked incident of disorder" had taken place in the Darnall area.
He added: "We are working hard to identify those individuals involved and we will take whatever measures we can to ensure the safety of our residents and businesses."
Police are appealing for witnesses.


I'm writing from the team apartment in Pyeongchang, venue for the 2018 Winter Olympics in South Korea.

We're here for the very first time to test out the new skeleton track and see what the venue has to offer and do vital prep work for when the team comes back to compete next year.
Each time a new Olympic venue is completed, there is a process of checking its safety and suitability for competition called 'homologation', where a select number of athletes are invited to try it out for the first time.
Some athletes were selected by random draw across the international field and those lucky few came here last year when things were much less finished to try out the track.
That completed successfully, the next stage is to hold a test event, which for skeleton is this year's final World Cup round.
The venue is looking great, almost finished and very clean and well presented. There are always small teething issues when everything's new as you might expect, but the organisers are helpful and doing their best to put on a great event.
The track is unique, with corner trajectories that have never been seen before, a long push start and technical questions all the way down.
There's no kreisel here (a 360 degree corner), but plenty of other challenges from the moment you jump on the sled to the finish line.
The longer your career as a slider, the fewer times you get to experience sliding a new track for the first time as they are only now built at new Olympic venues once every four years.
Obviously learning new tracks is a fairly common occurrence as a beginner when you first start competing and travelling, and at that time feeling out of your comfort zone almost becomes second nature as brand new scenarios are thrown at you constantly.
What makes this trip so unusual is that everyone on the international tour is experiencing being presented with a new track at the same time, so it's fascinating to see how people and teams approach getting to know it and getting over those fears of being at the start of a learning curve again.
I'm loving having a completely fresh challenge after a long, tough season of competing, and it's reminding me why I love the sport.
We came straight to Pyeongchang from the World Championships in Konigssee, Germany.
I left with real mixed feelings of how it had gone. On the one hand I had my best ever result at that track, 10th, but I was really hoping for better given that it was the most important race of the season.
I can't be disappointed with how I slid, I was consistent under pressure and finished seven places higher than in the World Cup there a few weeks previously.
Also, my strongest heat was cancelled when snow started to fall with only half the competitors having slid.
I always want races to be as fair as possible, but there's also an element of luck that comes with competing in an outdoor sport, and I've definitely felt the tough end of that this season on more than one occasion.
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So, when the heat that saw me jump several spots in the order was called off it was tough to come back and refocus for the second day of competition.
I still managed to climb three spots the second day, but I finished feeling very deflated that my best hadn't been good enough.
When you put all your energy and focus into something and it doesn't come off the way you hope, you can't help feeling that you've let down everyone around you who has worked so hard to get you there.
I'm just hoping that I'm saving all my luck for next season, and in the meantime learning as much as I can on the new Olympic track.
The final World Cup round is here in a week's time, so it'll be challenging to go back into competition mode one more time before the summer break.
But I'll definitely be looking for a strong result to round off the season and lay down a marker for next year.


Facebook has apologised for repeatedly restoring an account that posted stolen photos of children falsely claiming they had cancer.

The social network twice disabled the account following complaints, only to re-enable it hours later.
"These posts are clearly distressing for the families and this content has now been removed," a spokeswoman said.
"We apologise for the delay in taking them down."
The social network acted for a third time after the matter was brought to its attention by the BBC. It has not explained the actions of its complaints team.
One internet expert said the behaviour had been "bonkers" and called into question Facebook's safety procedures.
The BBC reported on Tuesday the case of a child from Cambridgeshire whose photos had been used alongside a fake plea for help.
"This little baby has cancer and he need money for surgery," the accompanying post stated.
It added that Facebook would donate money for every "like", comment or share of the message.
The picture was posted at the start of February. More than one million people responded.
Security experts said such tactics were often used by "like farming" scammers.
Perpetrators attempt to engage as many users as possible so that they can later target them with follow-up messages and/or sell on the profile page and its associated contacts to unscrupulous marketers.
The mother of the child - Sarah Allen from St Neots, Cambridgeshire - said she had been upset by the discovery.
"We had people messaging saying they had heard Jasper has cancer," she told the BBC.
"He doesn't. These were pictures from when he had chickenpox."
Facebook eventually deleted this post but - after overturning Tuesday's short-lived account block - left similar fake cancer posts featuring other children live.
The BBC determined they included a photo of a three-year-old girl from England, who was injured in a road accident in 2015. The image belongs to her parents.
"I need the photo to be removed," said the mother of the girl - who asked not to be named - when she was informed of its misuse.
"I am extremely upset about it."
Other images showed:
In addition, the account featured several photos of dead young children in coffins, claiming users would have "76 year of bad luck" if they scrolled past without liking or sharing the posts.
Facebook's community standards say it does not allow posts featuring images that infringe other people's copyright.
The company does not require each rights holder to make a claim before acting.
Facebook first disabled the account on 10 January after Mrs Allen had sent several messages to its complaints team, only for it to be made live again the next day.
The social network took the account offline again on Tuesday afternoon, but it was active again about five hours later.
The BBC questioned the decision early this morning. But it was not until about 15:00 GMT that the account was taken offline for a third time.
Cybersecurity expert Prof Alan Woodward said Facebook did not appear to have scrutinised the case closely enough despite the publicity it had already generated.
"Clearly anybody should have the right to appeal their account being taken down, but if it's returned up that quickly it doesn't show much due process has been taken in checking it out," said the University of Surrey lecturer.
"It's difficult not to conclude Facebook was doing the bare minimum here."


South Korea author Shin Kyung-sook has apologised after allegations she partly plagiarised a Japanese short story.

The allegations were made last week by novelist Lee Eung-jun in an article for Huffington Post Korea.
After an initial denial, Ms Shin has now admitted "it was right to raise" the issue in an interview with South Korean newspaper Kyunghyang Shinmun.
Ms Shin's 2009 book Please Look After Mom sold millions of copies and won the 2011 Man Asian Literary Prize.
Lee Eung-jun alleged that Ms Shin's Legend - part of a collection of short stories published in 1996 - included plagiarism of the 1961 story Patriotism by the late Japanese writer Yukio Mishima.
"After comparing the sentences in question in Yukio Mishima's novel Patriotism and those in Legend several times, I thought that it might be right to raise the plagiarism allegation," Ms Shin told Kyunghyang Shinmun in an article published on Tuesday.
"I desperately tried to recall my memory only to find that I haven't read Patriotism, but now I'm in a situation where even I can't believe my own memory."
Ms Shin said she would talk to her publisher about removing Legend from the book of short stories and take time for self-reflection.
"I sincerely apologise to the literary writer who raised the issue as well as all my acquaintances, and above all, many readers who read my novels.... Everything is my fault," she said.
She stopped short, however, of ending her writing career saying she cannot live without writing.


A man accused of trying to murder a trainee dentist in an apparent race revenge attack "acted like a lunatic" as he hacked his victim with a machete in a supermarket, a court heard.

Dr Sarandev Bhambra was set upon by 26-year-old Zack Davies with a hammer and machete in Tesco in Mold, Flintshire.
Mold Crown Court previously heard it was a revenge attack for the murder of Fusilier Lee Rigby.
Mr Davies, of Mold, denies attempted murder but admits wounding with intent.
Dr Bhambra was walking down an aisle in the store on 14 January when Mr Davies attacked him.
Shopper Leanne Jones said she heard the words "white power" and said Mr Davies "started to act like a lunatic and raised the machete above his head... he was striking him as hard as he could."
In a statement read to the court, another witness described hearing the words "white power" and "come here, this is for Lee Rigby".
Another woman, who was shopping with her four-year-old daughter, said: "He was shouting 'justice for the whites' as he was hacking with the machete... he was constantly striking on the Asian man's back."
She said Dr Bhambra had panic in his face and she thought he was "running for his life."
The court heard Dr Bhambra suffered two lacerations to his scalp which went down to the bone and a cut to his back which went down to the muscle.
The injury to his left hand caused major nerve, artery and tendon damage and he was in surgery for five hours.
Mr Davies told police: "It was me. I did it for Lee Rigby."
While being interviewed by police, Mr Davies said jihadi violence, the terror attacks in France and the murder of Lee Rigby were all on his mind.
He told officers he hoped his victim was "not seriously injured" but said he had harboured violent thoughts for more than a decade.
"Since I was 15 I have carried a knife every day and had thoughts of attacking people. Since I was 11 I have been holding back the violence" he told officers.
"It was a moment of madness, up to today I have been able to control these urges," he added.
Mr Davies said Dr Bhambra's religion was irrelevant, adding: "It was his appearance, just the way he looked... it was his racial appearance.
"Young white girls abused by Asians - that was also in the back of my mind."
Michael Adebolajo and Michael Adebowale were jailed for life in February 2014 for hacking Fusilier Rigby to death.
The trial continues.


Thousands of unwitting drivers fined for travelling down a bus lane with "inadequately lit" signage are to be refunded.

About 5,100 drivers caught during the hours of darkness in a two-month window will have their fines returned.
Newcastle City Council said bus lane warning signs were erected before new regulations - which do not require lighting - came into force.
The move will cost the authority Â£117,500 in refunds.
The two cameras on John Dobson Street have raised a total of Â£1.3m in fines since they were introduced in February.
Motorist David Crawford-Emery appealed to a tribunal on behalf of his girlfriend, after she received a fine for driving in the bus lane on John Dobson Street.
He won the appeal on the grounds "no offence had been committed", and shared the adjudicator's decision online, where it was shared more than 4,000 times.
"The adjudicator said the yellow and black advance warning sign that had been further down John Dobson Street was not sufficient on its own to give drivers advanced warning of this change.
"It said it was set back from the road, which it was, on the far edge of the pavement, it contained quite detailed information which would be difficult for a driver to fully take in."
Mr Crawford-Emery added: "I shared it for benefit of the fact I thought one or two of my friends may have been caught, and it went viral."
In a statement, the city council apologised and said any drivers due to receive a refund would be contacted directly.
"We are currently reviewing all adjudicators' decisions to see if we need to take any further action," it said.
"During this review we found that we issued 5,100 penalty charge notices during hours of darkness between 23 February and 22 April when the bus gate signs were not lit up.
"This happened because we were working to new Department for Transport regulations, which do not require lighting but which came into force later than we had anticipated."
Barry Speker, a senior consultant at Sintons solicitors, said those fined during daylight hours may have grounds to appeal and could affect "many thousands" of motorists and "hundreds of thousands" of pounds.


Pro12 leaders Connacht clinched a first competitive win at Thomond Park since 1986 with victory in the top-two clash.

Tiernan O'Halloran's opportunist try helped Connacht move 10-0 ahead but the deficit was halved by the break thanks to a maul try from Niall Scannell.
Connacht centre Craig Ronaldson fired over a penalty before a converted penalty try saw the hosts close to within a point.
Bundee Aki's late try sealed a win to take Connacht four clear at the top.
The opening points came with Ronaldson's penalty punishing a high tackle from Donnacha Ryan.
Munster missed 11 tackles in the opening 14 minutes and 22 by the interval - one of those defensive lapses saw hooker Scannell allow O'Halloran clean through for his try, which Ronaldson converted.
Munster were quick to respond and after successive line-outs Scannell plunged over from a well-controlled drive, although Ian Keatley was wide with the conversion attempt.
Ronaldson's penalty on the hour mark, set up by some excellent ruck work from captain John Muldoon, kept Connacht on course.
However, breaks from Keith Earls and Keatley got Munster into try-scoring range and Muldoon's impeding of Andrew Conway in the 22 resulted in a yellow card and penalty try, which Keatley converted.
With their lead cut to 13-12, Connacht missed an opportunity to steady their nerves when Ronaldson sent a kickable penalty wide from the right.
But rather than defend the one-point margin, they attacked with great ambition and got their reward three minutes from time when Robbie Henshaw's neat break on the Munster 22-metre line and flat offload sent Aki diving over past Conway.
Munster: Conway, van den Heever, Earls, Saili, Gonzalez Amorosino, Keatley, O'Leary, Cronin, N. Scannell, Botha, D. Ryan, Chisholm, Stander, O'Donoghue, Copeland.
Replacements: Hurley for van den Heever (50), Williams for O'Leary (65), Kilcoyne for Cronin (61), J. Ryan for Botha (41), Foley for D. Ryan (56). Not Used: O'Byrne, Coghlan, R. Scannell.
Connacht: Henshaw, O'Halloran, Aki, Ronaldson, Healy, A. MacGinty, Marmion, Buckley, Delahunt, White, Dillane, Muldowney, Muldoon, Connolly, Masteron.
Replacements: Leader for O'Halloran (68), Carty for A. MacGinty (45), Loughney for Buckley (54), Heffernan for Delahunt (61), Bealham for White (58), Naoupu for Dillane (63). Not Used: O'Brien, Porter.
Sin Bin: Muldoon (65)
Att: 12,000
Ref: Ben Whitehouse (Wales)


Middlesbrough have confirmed former Leeds United boss Garry Monk as their new manager.

Boro interviewed several candidates, but Monk emerged as the club's first choice and will be unveiled on Monday.
Monk, 38, left Leeds on 25 May after being unable to "reach an agreement" with new owner Andrea Radrizzani.
He managed Swansea City in the Premier League between 2014 and 2015 before guiding Leeds to a seventh-placed finish in the Championship last season.
Middlesbrough finished 19th and were relegated from the Premier League after winning just five of their 38 games under previous bosses Aitor Karanka and Steve Agnew.
Agnew took over from Karanka on 16 March on a temporary basis and could not prevent Boro going down, but is expected to stay on at the club in some capacity.
Former Southampton and Everton striker James Beattie, who worked with Monk at Leeds, is expected to be part of his coaching staff again at Middlesbrough.
Monk, who was appointed on a one-year rolling contract at Leeds in June 2016, had been expected to sign a new deal with the Yorkshire club after Radrizzani gained full control from Massimo Cellino.
However, Monk left saying he was unable to "agree a suitable way for us all to move forward together".


England manager Roy Hodgson says he does not fear anyone in the knockout stages, which is fair enough, but I do not see any teams being scared of playing us either.

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I do not want to be too negative but we have had three games at Euro 2016 so far and we were held by Russia, who are the worst team in the tournament, we beat Wales with a last-minute goal and we could not score against Slovakia.
I have not changed my mind about what I said on BBC One after the Slovakia game on Monday - I don't think Roy knows his best XI, or his best system, and that is where we are struggling.
It is not a total disaster finishing second in Group B, because we can still get a favourable tie depending on who is runner-up in Group F out of Portugal, Austria, Iceland and Hungary.
But, whoever we are up against, we are going to have to improve. Roy says we are ready to give someone a hiding, and I hope we do, but we are going to have to click in front of goal pretty soon or the worst will happen.
We are in the same half of the draw as Germany, Spain, Italy and hosts France, who would be our likely opponents if we reach the quarter-finals, but I am not looking that far ahead.
I think this tournament is wide open, which is a big positive for England, but at the moment we should only be thinking about how we will get through the last 16.
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I was very surprised at the number of changes Roy made against Slovakia, because it was a chance to gather some momentum. Particularly after the way we beat Wales, another good performance and win would have set us up for the tournament.
That is gone now, though. Instead we are back to asking a lot of questions about the England team and their tactics.
My concern, especially at this stage of the competition, is we do not have a reliable system to fall back on.
We have not got results playing in a 4-3-3 formation and I think part of the problem is that we do not have the players in our squad to use it effectively.
Other than Raheem Sterling, whose confidence seemed shot to bits in the first two games, we do not have any genuine wingers - our width has to come from our full-backs.
Daniel Sturridge has been out there on the right of our three-man attack but he does not really want to play out there. He wants to play in the middle and be a centre-forward.
Sterling has had his chance and didn't take it. Now we seem to be scrambling around to find a combination that works and it is all a bit confusing.
We need more guile in the final third to open teams up. Like Kyle Walker in our first two games, Nathaniel Clyne got forward well down that flank against Slovakia but they kept forcing us inside where there was no space and, in the end, we just ran out of ideas.
For our next game, in Nice on Monday, I would prefer we played a 4-2-3-1 or with a midfield diamond as it is a better fit for the players we have.
My diamond would have Eric Dier sitting, Dele Alli and Adam Lallana on the left and right, and Wayne Rooney just behind the front duo, who would be any two from Sturridge, Jamie Vardy and Harry Kane.
I called for Vardy and Sturridge to start against Slovakia - which happened, but with Sturridge on the right - and they struggled to make an impact. Whoever plays, they should both stay central.
It is ironic that, like a lot of people before the tournament, I was worried about our defence but it is our forwards who are finding things hard at the moment. It is just not happening for them.
We have seen a lot of teams at this tournament sitting very deep, especially in the final round of group games where they have been looking for a point to get through.
When you get to the knockout stage at a major finals, things are often very different but the standard at this expanded finals is not very high and some of the weaker teams will make it.
A lot of them are defensive-minded and, having seen England play they will probably be thinking they will stay deep, because we will not break them down.
If we can score a goal, that all changes, which is why we have to be more clinical when we do open teams up.
It is all well and good to say we have been dominating games in terms of possession and passing but if you do not score then that means nothing, as was proved by Leicester in the Premier League last season.
There have been some positives - our best three players so far have been Walker, Rooney and Dier, who I thought was superb with his range of passing against Slovakia.
But, in terms of positions, they are a full-back and two midfielders - one of them holding - which sort of sums up where England's problems have been in this tournament - in attack.
Alan Shearer was speaking to BBC Sport's Chris Bevan in France.
Who do you think should start? It's crunch time at Euro 2016 so pick your XI - and then share it with your friends using our team selector.


The wrecked Italian cruise ship, the Costa Concordia, is being towed to the port of Genoa for scrapping after a two-year salvage operation.

Its removal is one of the biggest ever maritime salvage operations.
The Concordia struck a reef off the Italian island of Giglio in January 2012 and capsized, killing 32 people.
Captain Francesco Schettino has denied charges of multiple manslaughter and abandoning ship, which could see him jailed for up to 20 years.
The Costa Concordia was re-floated nine days ago and is being kept above the surface by giant buoyancy chambers. More than a dozen vessels will help to tow the ship.
The wreck was hauled upright in September last year but was still partially submerged, resting on six steel platforms.
Sirens on nearby boats wailed and bells on Giglio tolled just before two tugboats pulled the vessel away.
Italian civil protection service head Franco Gabrielli told the Reuters news agency that "victory" could only be declared when the ship was in sight of the port of Genoa.
The cruise ship is being towed to Genoa at two knots, almost at walking pace, with an escort of more than a dozen tug boats.
The journey, which is expected to take four days, began shortly before 09:00 local time (07:00 GMT).
Senior salvage master Nick Sloane said early on Wednesday that everything was going according to plan.
However, French ecology minister Segolene Royal has said she will monitor the ship's movement from Corsica. Residents on the island fear that any oil leak from the cruise ship could cause significant environmental damage.
The Concordia is set to sail 25km (15 miles) from Corsica and close to the islands of Elba and Capraia before its expected arrival in Genoa late on Saturday.
A survivor of the tragedy told Reuters that initially he saw the area where the ship sunk as "a place where I saw tragedy strike", but over time his view had changed because it was a miracle that 4,000 people were saved.
Investigators are still looking for the body of Indian waiter Russel Rebello, whose body is the only one not to have been found.
The Costa Concordia's owners, Costa Crociere, estimate the operation to remove the wreck from the reef and tow it for scrapping will cost 1.5bn euros (£1.2bn; $2bn) in total.


Pupils at a County Durham school have shown the red card to the Football Association over its advice to try and get more girls into the sport.

A document on its website included suggestions girls should be offered "colourful, nice smelling" bibs and pink whistles.
Football is popular with girls at Lumley Junior School and some wrote to the FA taking issue with the tips.
The FA said the document was created after research and feedback.
The opening suggestion is to: "Advertise in places where girls go i.e. coffee shops or on the back of toilet doors."
Deputy head Carol Hughes came across the document while researching resources to use in writing week.
"I was absolutely horrified, and actually laughed out loud at some of the suggestions," she said.
"I took it to another teacher and she had the same response."
Some of her year six pupils wrote to the FA, saying although the document was done with the best of intentions, they found it insulting.
"We aren't brainless Barbie dolls. We don't all like the same colour - pink," one of the pupils said.  Another added: "We don't need pink whistles and we don't have big mouths, so why do we need a big mouth water bottle."
Another member of the class said: "The stereotypical thought of advertising in coffee shops as 'it is where girls go' is disgraceful." While a fourth pupil said: "I play for Middlesbrough and know countless girls that are interested in football and not one agrees with this."
A spokesman for the FA said: "The FA is committed to doubling female football participation by 2020 and to growing the women's game at all levels, from elite to grassroots.
"The document was created following research into women and girls playing football, with feedback from both participants and non-participants.
"We're very pleased to see how many girls at the school play football and the passion for the game that they clearly have."
Durham Women FC player, Helen Alderson, said she thought the FA had been naive.
She said: "If you look through the whole document some of it is alright - they've tried to put themselves in the shoes of girls and women.
"I'm a little bit disappointed in the FA - they've been naive rather than sexist.  If they reviewed the document fully they might pull it."


Two gunmen opened fire at a hotel close to the pyramids of Giza outside Cairo, as tourists boarded a coach, Egyptian security sources have said.

There were no casualties in the attack, which caused some damage to the Three Pyramids Hotel, and the gunmen were arrested soon afterwards, they added.
The driver of the bus told the BBC that the tourists included Israeli Arabs.
Egypt has been battling a jihadist insurgency since the military overthrew President Mohammed Morsi in July 2013.
Militants, largely based in the Sinai Peninsula, have killed hundreds of security personnel and civilians, set off bombs in the capital and attacked Western targets.
In June, gunmen shot dead two policemen a few hundred metres from the pyramids, Egypt's most visible tourist attraction.
An affiliate of the jihadist group Islamic State (IS) has also claimed it planted a bomb on a Russian passenger plane that crashed in Sinai in October, killing all 224 people on board. However, Egypt says it has found no evidence of terrorism.


Scotland's plan was, in line with the words of their pre-match anthem that echoed thunderously around Celtic Park, to send England homeward to think again.

Instead, on England's first visit north of the border since 1999, the "Auld Enemy" outclassed Scotland to take another step on the road to rehabilitation after the misery of the World Cup in Brazil.
England have not tested their recovery from the trauma of South America against any of football's elite, so the manner in which they have bounced back must be judged in that context - but a clean sweep of victories since that final meaningless, goalless group game against Costa Rica in Belo Horizonte is still a very impressive statistic.
England's 3-1 win in the intimidating surroundings of Celtic Park, and against a Scotland team on an upward curve under manager Gordon Strachan, was arguably their most complete since the World Cup.
Manager Roy Hodgson saw his side open with an intensity that is sometimes missing from the opening phases of their games and maintained it throughout. Scotland boss Strachan was fulsome in his praise for England.
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The tale of the tape reads played six and won six since the World Cup - with 15 goals scored and only two conceded - including four Euro 2016 qualifiers against Switzerland, San Marino, Estonia and Slovenia bookended by friendly wins against Norway and now Scotland.
England have not conceded a goal in the first half of any of their last seven games and one of those two goals conceded was Jordan Henderson's deft header into his own net against Slovenia.
There can be no question England's cause has been helped by a kind Euro 2016 qualifying draw, but the visit on to footballing enemy ground in Glasgow was perhaps a more realistic test of their standing than most of their qualifiers.
And judged on that, the comprehensive manner of this win may have told Hodgson more about his players than routine victories in qualifiers.
Scotland may have had only two Premier League players in their starting line-up, Hull City's Andrew Robertson and Everton forward Steven Naismith, and played like a team whose main business for this international break had been concluded with the Euro 2016 qualifying win against the Republic of Ireland, but England did not hang around to wait to find out.
In a predictably hostile atmosphere they went straight on to the front foot and never allowed Scotland into the game. It was a test of their mettle, their nerve and their stomach for the fight and they came through with pass marks.
And it was a win achieved so comfortably against a Scotland team that ensured England arrived in a country with rapidly increasing optimism, especially after the vital 1-0 Euro 2016 qualifier win against the Republic of Ireland on Friday.
Hodgson praised the maturity of his players "under the magnifying glass", saying: "I'm not sure they needed to prove they were real men. I knew that. But this was a game played in a real goldfish bowl."
Let's not get carried away as England are still strictly second tier when it comes to world football's elite - but it is churlish to offer too much criticism of such a run of wins when the last time they achieved something similar was in June 2006.
Since the World Cup, Hodgson has made tweaks to his squad and his team and there were optimistic signs for the future amid the tumult of Celtic Park.
Southampton's Nathaniel Clyne was highly impressive again, both in defence and attack. There is an opening for a right-back in England's team and he has walked through it. He has shown enough to warrant a good run in the team.
Jack Wilshere was England's best player against Scotland, a commanding display characterised by the raking, driven pass that created the first goal for Alex Oxlade-Chamberlain - oddly his first assist on his 26th international appearance.
The enthusiasm for the use of Wilshere at the base of England's diamond must be tempered by the simple truth that he has not yet faced top-class opposition in that role. This is the acid test, but he dictated affairs here.
Oxlade-Chamberlain was another bonus, scoring for the first time since his goal in the 2-2 draw against Brazil in the Maracana in June 2013.
Another significant stat to help his case may be that he is something of a lucky charm for Hodgson. England have never lost a game in which he has figured, with a record of played 20, won 14 and drawn six.
The debate raged about whether Wayne Rooney could be considered an England "great" in the build-up to his 100th appearance when he played against Slovenia on Saturday, but what is not a matter for serious discussion is his worth to this team and manager Roy Hodgson.
The numbers are out there. The two goals against Scotland edged him ahead of the great Jimmy Greaves and into third place on his own in the all-time standings with 46, two behind Gary Lineker and three behind all-time record holder Sir Bobby Charlton.
Of current significance is his record of 18 goals in 28 appearances under Hodgson. He has now scored in six of his last seven England starts, scoring seven goals in total.
Here in Scotland he gave a performance of maturity and class, scoring twice and setting the tone for England's display from the first whistle with his intense, committed - but never out of control - approach.
And in the days before the game, captain Rooney made it his business to address the young players in England's squad to make them aware of the special, hostile atmosphere they would face. Forewarned is forearmed and here he showed a sure touch with his team-mates.
In the current England set-up, he is indispensible.
Just a couple on an otherwise highly satisfactory night for England and Hodgson.
Why was Everton's Ross Barkley given a walk-on part of a couple of minutes at the end? What was the point? Surely Celtic Park was the ideal place to give this lavishly talented youngster at least 45 minutes to test out his temperament and decision-making.
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And will the return of Stewart Downing to England's colours for the first time since he played in Hodgson's first game in charge in Norway in May 2012 be a "blink and you missed it" affair?
He had an undistinguished 45 minutes, looking nothing like the player who has excelled for West Ham United this season.
However, rather than playing in the more central position he occupies under Sam Allardyce for his club, Downing was shunted out to the left in a 4-3-3 formation and consequently looked like the under-achiever of the past.
And Liverpool's Rickie Lambert (barely causing a ripple at Anfield this season) on for 11 minutes? Why not give West Bromwich Albion's Saido Berahino a brief taste of what might be expected of him at international level?
England resume in March with what should be another routine Euro 2016 qualifier at home to Lithuania but then face a stern test with a friendly in Italy four days later.
The diary of fixtures, mainly the remaining qualifiers, merely reads like a smooth passage to France and perhaps even the opportunity for Hodgson to indulge in some experimentation with the possibility of early qualification.
Another friendly against the Republic of Ireland in Dublin on 7 June will sharpen the reflexes for a visit to Slovenia a week later - but this excellent win in Scotland ensures 2014 will end with England in good spirits.


Australia is refusing to comment on the fate of more than 200 Tamil asylum seekers reportedly intercepted at sea to the north-west of the country.

It is believed two boats carrying the asylum seekers were stopped by Australian authorities in the Indian Ocean and that some passengers were handed over to the Sri Lankan navy.
Refugee campaigners say it is a violation of international law.
They say at least 11 of those on board had been tortured in Sri Lanka.
Australia has been taking a tough approach on asylum seekers who try to reach the country by perilous sea journeys.
Hundreds of would-be migrants have died trying to make their way to Australia by boat in recent years.
The government has made no comment for what it says are "operational reasons" and will neither confirm nor deny the existence of the two boats carrying Tamils from Sri Lanka, says the BBC's Phil Mercer in Sydney.
But Australian media say that some have already had their refugee claims rejected and have been transferred to the Sri Lankan navy, he adds.
Forcing asylum seekers back to their country of origin without properly investigating their claims is a flagrant breach of the Refugee Convention and international law, the Refugee Council of Australia said.
Chief executive Paul Power said: "For asylum seekers, this is a matter of life and death, particularly in Sri Lanka which has a long history of political violence on a scale unimaginable to Australians."
Ministers say, however, that Australia is upholding its international obligations.
Tamil Refugee Council spokesman Aran Mylvaganam said he had spoken to relatives of some of those on the boats and that at least 11 had been arrested by Sri Lanka's intelligence forces "and had been tortured".
The UN refugee council earlier this week expressed "profound concern" about Australia's handling of the asylum seekers.
It has been six months since a vessel carrying refugees reached Australia after the military was called in to turn boats around.
Under current Australian policy, most asylum seekers who try to make their way to Australia by boat are sent to detention camps in Papua New Guinea or Nauru. If found to be refugees, they will be resettled there, not in Australia.
Australia says its asylum policy - which is also widely believed to involve towing back boats to Indonesian waters - is aimed at saving lives.
Our correspondent says stopping refugee boats from reaching the country was one of the main campaign pledges of Prime Minister Tony Abbott.
Sri Lanka has been under heavy international pressure over alleged human rights violations during the final phase of the war against Tamil separatists which ended in 2009.
Rights groups say Tamils still face violence at the hands of the military.


Papers belonging to Mahatma Gandhi, Hanif Kureishi and other leading South Asian figures are going on display.

'Documenting Histories' will look at the impact of South Asian culture on Birmingham and the Midlands, 70 years after India declared its independence.
Official records from the East India Company will also be available.
The exhibition is being put on by the Library of Birmingham and the British Library, who have been given £91,700 from the Heritage Lottery fund.
According to the 2011 census, 9% of Birmingham's population was born in Bangladesh, India or Pakistan - numbering about 85,000 people.
More on this and other stories from Birmingham and the Black Country
Workshops and other events will be held throughout the year to get families to show how the relationship between the UK and the region has shaped their lives.
Birmingham City Council has declared 2017 as the Year of South Asian Culture to celebrate the impact of communities from the region.
Vanessa Harbar, head of the Heritage Lottery Fund in the West Midlands, said the "fascinating and timely project" would allow people to "gain a better understanding" of Birmingham's history.
Ian Ward, deputy leader of the city council, said: "This year, in particular, presents a great opportunity to celebrate the contribution of South Asian culture to Birmingham's past, present and future."
The exhibition will open in July.


Northern Ireland pair Holly Nixon and Alan Campbell will be among the British rowers aiming to press their claims for Rio Olympic berths at this weekend's European Championships in Germany.

London 2012 bronze medallist Alan Campbell will hope a strong showing in the single scull will help to secure a place at a fourth Olympic Games.
Enniskillen woman Nixon, 22, will be part of Britain's quadruple scull team.
The event is the last event ahead of the final Olympic qualifier in Lucerne.
Nixon, Tina Stiller, Jess Leyden and Rosamund Bradbury finished fourth at the World Cup regatta in Varese last month and will hope to be in the medals in Brandenburg.
"This weekend is going to give us more of a glimpse of what could turn up at the Olympic qualification regatta in Lucerne," said Nixon.
"I think things are going well so far. Having more time in the crew is always a positive and we are making the most of that time together.
"I feel really lucky each day I get to go out with the girls. I am learning so much from them."
Campbell, representing Britain for a 10th successive year, will be facing a strong field in the single scull.
"I've seen the entry list and pretty much everyone you would expect is there," said the 32-year-old.
"Ondrej Synek is there, he's a three-times world champion now, and what Croatia's Damir Martin did in winning the World Cup in Varese last month was pretty exceptional.
"There are also a lot of new guys coming through and some people who are still looking to qualify for Rio, so they will really be on their game."
Campbell's fellow Coleraine Olympic medallist Peter Chambers will compete in the lightweight men's four this weekend.
Chambers' brother Richard has withdrawn from the lightweight men's double scull with Will Fletcher as he continues his recovery from a hand injury but another Coleraine man Joel Cassells will be in action in the non-Olympic lightweight pair with Sam Scrimgeour.
Cassells and Scrimgeour are the defending world champions in the class.


Turkey's President Recep Tayyip Erdogan has rejected criticism by monitors who say the referendum campaign fell short of international standards.

"Know your place," he said, adding that he did not accept the comments.
The observers said Mr Erdogan had been favoured by an "unequal" campaign. In the referendum, voters gave sweeping new powers to the president.
The narrow vote was ruled valid by Turkey's electoral body, despite claims of irregularities by the opposition.
Mr Erdogan's push for an executive presidency succeeded with 51.4% voting for it.
Meanwhile, the country's top security body backed the extension of the state of emergency for three months.
The measure, introduced after a failed coup last July, was set to expire in two days. Turkey's cabinet is to meet later on Monday to decide on the issue.
Despite saying that the voting day was "well administered", the Organization for Security and Co-operation in Europe (OSCE) and the Council of Europe criticised the campaign, saying:
"In general, the referendum did not live up to Council of Europe standards," said Cezar Florin Preda, head of the Council of Europe delegation.
The council is a pan-European human rights body of which Turkey is a member.
The monitors also criticised a late change by electoral officials that allowed voting papers without official stamps to be counted. They said this move "removed an important safeguard and were contested by the opposition.
But the head of Turkey's electoral body, Sadi Guven, said the unstamped ballot papers had been produced by the High Electoral Board and were valid. He said a similar procedure had been used in past elections.
Turkey divisions exacerbated
The referendum in numbers
Addressing supporters in the presidential palace in Ankara, Mr Erdogan said that Turkey did not "see, hear or acknowledge the politically motivated reports" of the monitors.
The result, he said, ended the debate on changing the constitution and creating an executive presidency, adding that the process of implementing the reforms would now begin.
He also said the country could hold a referendum on its long-stalled EU membership bid.
Additionally, Mr Erdogan said he would approve the death penalty if it was supported in a referendum or a bill was submitted to him through parliament. This would end Turkey's EU negotiations.
Earlier, Turkey's foreign ministry said the remarks by the monitors lacked impartiality. "Saying the referendum fell below international standards is unacceptable," it said in a statement.
The main opposition Republican People's Party (CHP) has demanded a recount of 60% of the votes. Its deputy head said the result should be annulled altogether.
The pro-Kurdish Peoples' Democratic Party (HDP) also challenged the vote.
Profile: Erdogan's rise to power
Turkey referendum: Key reactions
This was a damning verdict by the observer mission.
From biased media coverage to a misuse of administrative resources by the president and government; and from restrictions on free speech to a decision to accept unstamped ballots, which "contradicted the law"; the election observers concluded that the referendum did not fulfil international standards. So what now?
It's sure to embolden the opposition in its attempts to challenge the results. But that is an uphill struggle in a country where the state machinery is so heavily controlled by the president and his inner circle and where around 80% of the media is pro-government, pushing its interpretation of the facts.
What's more certain is that it'll shape the response to the referendum by European leaders and officials. They won't rush to congratulate a victory whose legitimacy has been placed in serious doubt. And as government supporters double down, convinced of their win, the chasm between Turkey and the west shows no sign of narrowing.
Erdogan's Turkey: The full story
Turnout for the divisive vote was high - 85%. Mr Erdogan won in his central Anatolian heartland and on the Black Sea coast.
But he lost in the districts containing Turkey's three largest cities.
In Istanbul, the largest city, and the capital, Ankara, the vote was very close. But in Izmir, the third-largest city, the margin was a much higher 68.8% No.
Along the Aegean and Southeast Anatolia coast - which is home to many Kurds - most districts also rejected the changes.


Labour's "ambition" is to write off all student debt, which would cost £100bn, shadow education secretary Angela Rayner has said.

The Labour MP said it was a "huge amount" and the party would not commit to doing it "unless we can afford to".
The Conservatives said it was a "shambolic" proposal, which Labour had no idea how to fund and would lead to higher taxes.
Labour has pledged to scrap university tuition fees if it wins power.
But leader Jeremy Corbyn went further in an interview with the NME during the election campaign, suggesting existing debts could be wiped.
He told the music magazine: "There is a block of those that currently have a massive debt, and I'm looking at ways that we could reduce that, ameliorate that, lengthen the period of paying it off, or some other means of reducing that debt burden.
"I don't see why those that had the historical misfortune to be at university during the £9,000 period should be burdened excessively compared to those that went before or those that come after. I will deal with it."
The Greens were the only party at the general election to include a commitment to wipe all student debt in their manifesto.
Quizzed by the BBC's Andrew Marr on how much it would cost, Ms Rayner said: "It is a huge amount, it is £100bn, which they estimate at the moment, which will increase.
"It's a huge amount of money but we also know a third of that is never repaid."
Ms Rayner said Mr Corbyn had said it was an "ambition", but she added "we will not announce that we're doing it unless we can afford to do that".
She added: "I like a challenge, Andrew, but we've got to start dealing with this debt crisis that we're foisting on our young people. It's not acceptable.
"They are leaving university with £57,000 worth of debt, it's completely unsustainable and we've got to start tackling that."
Last month, the Student Loan Company said that outstanding debt on student loans had increased by 16.6% to £100.5bn at the end of March.
Only about a third of the students who have taken out £9,000-a-year loans are expected to pay them back fully, meaning the government will have to pick up part of the bill.
Lord Adonis, who came up with the student fees policy as Tony Blair's policy director, has called for them to be scrapped or vastly reduced, saying in an article for the Guardian that he had never meant to create a "Frankenstein's monster of £50,000-plus debts for graduates on modest salaries".
He blamed "greedy" university vice-chancellors, who successfully lobbied the coalition government to increase the £3,000 cap on fees to £9,000.
Conservative First Secretary of State Damian Green, who is effectively Theresa May's second-in-command, has called for a "national conversation" on tuition fees, to consider whether they should be paid out of taxes.
Angela Rayner has previously called on the government to reverse the abolition of student maintenance grants to help the most disadvantaged students.
She also wants to reduce the interest rate that students have to pay on their loans, which has gone up to 6.1%.
Asked by Andrew Marr if fewer working class youngsters were getting into university education as a result of tuition fees, she said: "I don't believe that that's the case actually, but I do believe that many working class and part-time and older mature students are actually leaving university."
Conservative MP Luke Hall said Ms Rayner's comments contradicted Mr Corbyn's claim that fewer people from disadvantaged backgrounds were going to university.
He said: "The truth is that the number of people going to university from disadvantaged backgrounds has never been higher.
"Now Labour are making shambolic promises to spend £100bn extra, without any idea of how to fund it, that could only be paid for through higher taxes on families.
"This government is committed to making sure that everybody has the chance to go to university no matter their background, so that we can build a country that works for everyone."


An MP who wrongly claimed Wolverhampton City Council had spent £1,428 on pizzas in India has been accused of failing to carry out basic checks.

Conservative MP Paul Uppal revealed the figure, which he took from the Spotlight on Spend website, on BBC WM.
But the 1,428 actually referred to rupees and equates to just £14.
Wolverhampton City Council said Mr Uppal had been left with "egg on his face" - but he pointed out the sum had been listed with a pound sign online.
Councillor Andrew Johnson, Wolverhampton City Council's cabinet member for resources, said: "Local government finances can be complex, but I would have expected Paul Uppal, as a member of parliament, to carry out basic checks with the council before going public with these figures and getting egg on his face.
"We would have been more than happy to assist him to understand the numbers."
Shadow housing minister Emma Reynolds, the Labour MP for Wolverhampton North East, went further, calling for an apology.
But Mr Uppal, who represents Wolverhampton South West, said the mistake was not his.
"It's there in black and white," he said.
"The council has thanked me for pointing it out."


Two more people have been arrested in connection with the fatal shooting of Assel Al-Essaie after armed police stopped a vehicle on the Sheffield Parkway.

Mr Al-Essaie, 23, died in hospital after being shot in the chest in Daniel Hill, Walkley on Saturday 18 February.
South Yorkshire Police has not released any further details of those arrested.
Five people previously arrested in connection with the shooting have been released on bail.