New information suggests a man who disappeared almost 25 years ago may have been killed and buried on land in Merseyside, police say.

Steven Preston went missing on 18 September 1992 from his home in Wirral.
New information suggests Mr Preston, then 23, may have "been murdered and buried in a specific area near junction 5 of the M53", said Supt Ian Hassall.
Officers are carrying out an "extensive land search" in the Eastham area of Wirral, Merseyside Police said.
Supt Hassall said Mr Preston was last seen by his mum, Isobel, as "he waved from his bedroom window to her when she left for work at 08:45" BST from their home in Heath Road, Bebington.
"Isobel said there had been no arguments and Steven had left home without his jacket or prescription for medication he was on", he said.
He was reported missing five days later but was never found.
"Today a painstaking search is being carried out following information recently obtained by detectives, which suggest that Steven may have been murdered and buried in a specific area of land near to junction 5 of the M53 motorway", Supt Hassall added.
Mr Preston's sister, Jane, said she was "anxious to find out what happened to her brother after all these years."
She said he was "a gentle, kind and funny lad" who "didn't have a nasty bone in him."
"He adored my mum and it destroyed her when he disappeared. She knew instantly that he wouldn't have just left and never contact her again and that something awful must have happened to him", she said.
Supt Hassall appealed for information, saying: "Sadly, Steven's mother, Isobel, and half-brother, Michael Connolly have died since his disappearance, never knowing what had happened to him.
"A young man in 20s doesn't just leave home and vanish into thin air. Somebody, somewhere must know where he is, or what happened to him."


Kieran Tierney says he is happy to test his versatility for Scotland after playing three different positions in his last three international matches.

The left-back played his normal role in the defeat in Slovakia, right-back in the win over Slovenia and centre-back in Saturday's 2-2 draw with England.
"Being told you are playing centre-back and you have not done it too many times, it's hard," Tierney said.
"It's a new challenge, like when I was right-back, but I like new challenges."
Celtic's Tierney played alongside Christophe Berra and Charlie Mulgrew as part of a back three on Saturday at Hampden, head coach Gordon Strachan having adopted a new approach against the unbeaten Group F leaders.
The Scotland defence was breached by second-half substitute Alex Oxlade-Chamberlain before two Leigh Griffiths free-kicks in 87 and 90 minutes had the hosts on the brink of an unlikely win.
England skipper Harry Kane, however, ensured the points were shared with a stoppage-time equaliser.
Tierney was solid in his new role and made one goal-line clearance from the England captain.
"I tried to do my best," said the 20-year-old. "The last five minutes was a roller-coaster - obviously Griff's great two free-kicks and the sucker punch at the end, which left us gutted.
"But I think we can be proud of the effort we put in."
The draw felt like a defeat to Tierney due to the timing of Kane's strike, but he said time may change his perception of a result that left Scotland six points behind leaders England, three behind Slovenia and four behind Slovakia with four fixtures remaining.
"I hope it is the case because the boys put everything into it," Tierney said.
"We trained all week and everyone in the squad gave 100% against England, so it was good that way.
"We will get on with it and look forward to the remaining games in the group."


Patients are being left stranded on trolleys for hours and forced to have treatment in corridors due in part to the loss of hospital beds, nurses say.

The Royal College of Nursing says feedback from more than 1,200 staff paints a "worrying picture", with patients regularly being in ambulances or held in a queue.
The union warned the NHS risked going backwards unless ministers got a grip.
The government said there were enough beds for this not to be happening.
Of the 1,246 nurses and healthcare assistants who replied to an RCN request for feedback, a fifth said providing care in corridors had become a daily occurrence.
Half said they had encountered patients facing long waits on trolleys - with some aware of people being left for 24 hours without a bed.
The RCN said that was putting patients at risk by potentially leaving them without access to essential equipment such as oxygen supplies and heart monitoring equipment as well as compromising their privacy and dignity.
Other problems highlighted included ambulances being forced to queue outside A&E units and patients being put in unsuitable wards.
The RCN said the crisis was being caused by a combination of staff shortages, the long-standing drive to reduce the number of beds in hospitals and the rise in A&E admissions.
The union said as a first step the government should call a halt to the reduction in beds. Over the last 10 years, the number of acute and general beds available has fallen by a fifth to just over 100,000.
This has been partly done because of advances in medicine which means patients need to spend less time recovering in hospital and can get a wider range of treatments in the community.
RCN general secretary Peter Carter said frontline staff were being placed under "huge stress", adding the NHS was at risk of going "backwards".
"Treating patients on corridors and areas not designed for care is a high-risk strategy, which can have a serious impact on patient care.
"Patients need to be able to interact with staff, to be able to reach call bells and to know they are visible."
Mike Farrar, chief executive of the NHS Confederation, which represents hospitals, said the problems identified should not be happening.
But he added hospitals were facing a struggle because of "growing financial pressure and significant structural upheaval".
Health minister Simon Burns said: "There is no excuse for patients to be left waiting on trolleys.
"The NHS has beds free and available, and hospitals should be supporting their nurses to ensure that patients are admitted to them quickly. We will not hesitate to take action where we find hospitals failing to do so."


All-night vigils will be held across the UK next summer to mark the centenary of the Battle of the Somme in World War One.

A national vigil is to be held on 30 June at Westminster Abbey, London, with overnight events being held in Edinburgh, Cardiff and Co Down.
There will also be a commemorative service the following day at Manchester Cathedral.
More than 600,000 British and French troops died during the WW1 battle.
Announcing the commemorations, Culture Secretary John Whittingdale said: "We must never forget the scale of what happened at the Somme.
"More died on the first day of battle than any other day of the First World War. Almost every family in the country was touched by the devastating losses.
"I hope people of all generations up and down the country will have the chance to attend an event and honour the bravery of those who sacrificed so much."
The overnight vigils on 30 June will take place at:
There will also be a programme of overnight events at the Imperial War Museum in London that night.
The commemorative service will be held on 1 July at Manchester Cathedral, followed by a procession through the city to Heaton Park.
And further events will take place at Commonwealth War Graves Commission cemeteries and memorials.
The government had already announced plans for an event on 1 July at Thiepval in northern France, where a memorial holds the names of 72,000 fallen soldiers who have no known graves.
Around 10,000 people are expected to attend next year's event at the memorial, with 8,000 selected by ballot.
The Battle of the Somme began on 1 July 1916 and did not end until 18 November that year.
The aim of the offensive was to achieve a clear victory for the British and French, but the campaign turned into a stalemate, with soldiers struggling to gain any ground after heavy rains in October.


The German Chancellor, Angela Merkel, has said there can be no talks on Brexit before the UK formally begins the process of leaving the EU.

While accepting the UK needed time, she added it should not be a "long time".
Mrs Merkel is due to meet French and Italian leaders later in Berlin, with the speed of negotiations for the UK's exit high on the agenda.
UK Prime Minister David Cameron has confirmed the UK is not ready to begin the formal withdrawal process.
Earlier, Chancellor George Osborne issued a statement to try to calm markets. UK shares remained uneasy in the wake of the vote.
Billions more dollars were wiped off the value of shares in Europe and on Wall Street as a result of market uncertainty on Monday. London's benchmark share index was down 2.75% while Germany's leading index fell by 3%.
Last Thursday, the UK voted 52-48 in favour of leaving the EU in a historic referendum, throwing the economy and politics into turmoil.
US Secretary of State John Kerry has said his country's "special relationship" with the UK will be maintained. "The vote did not come out the way US President [Barack] Obama and I had expected but that's democracy," he told reporters in Brussels.
"The reality is that a majority of British citizens voted to leave... so I await a communication about Article 50 [the formal trigger for withdrawal] from the UK addressed to the EU," Mrs Merkel said.
"We should not wait a long time. I do understand that the UK will consider things for a while. There cannot be any informal negotiations until we get that message from the UK.
"We can't have a permanent impasse," she was quoted as saying by Reuters news agency.
Once the UK invokes it, Article 50 of the Treaty of Lisbon sets out a two-year timetable to reach an exit deal. But UK PM David Cameron, who will step down by October, says he will leave the timing to his successor. He is due to make a special address to parliament later.
The Leave campaign says there is no need to rush the UK's exit.
France and Germany have insisted they are in "full agreement" on Brexit, although French Finance Minister Michel Sapin said on Monday this meant Britain should "go quickly".
Mr Cameron took to the floor of the House of Commons to say he had spoken to European leaders and told them "the British government [would] not be triggering Article 50 at this stage".
"Before we do that we need to determine the kind of relationship we want with the EU," he said.
He repeated his promise to stand down as prime minister this year and said it would be up to his successor to invoke Article 50.
The chancellor, who backed Remain, tried to reassure financial markets that the UK was in a strong position to tackle the inevitable volatility.
Despite suggesting before the vote that an emergency budget would be needed, he indicated that this would not now be an immediate priority, preferring to leave any adjustments to the economy to the new PM.
He appeared to rule out resigning in the near future.
Boris Johnson, the leading light of the Leave campaign, used an article in the Daily Telegraph to try to soothe British fears.
"EU citizens living in this country will have their rights fully protected, and the same goes for British citizens living in the EU. British people will still be able to go and work in the EU; to live; to travel; to study; to buy homes and settle down," he said.
He also suggested the UK would still have access to the EU's single market, a remark quickly challenged by the German Business Institute and Merkel ally Michael Fuchs, MP.
Mr Fuchs said: "It will be possible, of course, but not for free - you have to see with Norway, with Switzerland, you have to pay a certain fee. And the per capita fee of Norway is exactly the same as what Britain is now paying into the EU. So there won't be any savings."
Labour faced more turmoil, with further resignations of shadow ministers on Monday. Twenty-three of the 31 members of the shadow cabinet have now gone.
Mr Corbyn has announced a new team but faces a possible no-confidence vote.
Nicola Sturgeon, the first minister of Scotland, which voted 62% for Remain, told the BBC the Scottish parliament could try to block the UK's exit from the EU.
She also confirmed a second Scottish independence referendum was back on the table.
Monday: Angela Merkel holds crisis talks in Berlin, first with EU President Donald Tusk, then with Mr Hollande and Mr Renzi (statement to media expected at 18:30 local time, 16:30 GMT).
Tuesday: Extraordinary European Parliament session in Brussels on Brexit vote 10:00-12:00 (08:00-10:00 GMT), including speeches by Mr Tusk, European Commission President Jean-Claude Juncker and party leaders, probably including UKIP's Nigel Farage. There is also an EU summit (European Council) in Brussels, at which David Cameron will brief the other EU leaders over dinner, from 19:45 (17:45 GMT), explaining the political fallout in the UK
Wednesday: Second day of EU summit will feature breakfast talks between 27 leaders - Mr Cameron not attending. Talks focus on UK's "divorce process" as stipulated by Article 50, and Mr Tusk will "launch a wider reflection on the future of the EU"; press conferences in afternoon.


The head teacher of a primary school has appeared in court charged with voyeurism and making indecent images of children.

Ashley Yates, 45, has been suspended from The Tynings Primary School in Staple Hill, South Gloucestershire.
Mr Yates, from Filton, was remanded in custody after appearing at Bristol Magistrates' Court
He is charged with three counts of making indecent photos and two counts of voyeurism.
In a statement on the school website, Sarah Warren, chair of governors, said: "While the investigation is under way I am legally bound not to comment further.
"I hope you will understand that, despite your obvious concerns, we cannot go into any further detail at the moment and we will remain guided by police in terms of our comments as we do not want to jeopardise their work."
She also asked parents not to speculate on social media about the case.
A South Gloucestershire Council spokesperson said: "We can confirm head teacher Ashley Yates has been charged with making indecent images of children and voyeurism, which is subject to a police investigation.
"We are working closely with the school to ensure that parents and staff are being supported."
Mr Yates is due before Bristol Crown Court on 19 July.


Council tenants in Cardiff could lose the right to buy their home under plans to address the shortage of rented homes in the city.

The council said there were 8,300 people on the waiting list for social housing - a figure set to increase further in the next five years.
It has 13,470 properties, which has fallen from 23,000 since 1985, largely due to the Right to Buy legislation.
The Welsh Government has already said it wants to abolish it in Wales.
Most council tenants have the right to buy their homes after five years and receive a discount of up to Â£8,000 on the value.
But the authority said there was a "very high level of housing need" in the city which needed to be addressed.
Susan Elsmore, cabinet member for health, housing and wellbeing, said the council estimated it would need an extra 2,024 affordable homes each year for the next five years and research showed more than 5,000 families were living in overcrowded or unsuitable homes.
"Every month, 450 new applications for housing are received but only 860 council properties became vacant and available to let in the whole of 2015/16," she said.
"Every house sold through the [Right to Buy] scheme is a home that is no longer available to a family in need so for this reason, we will consider suspending the scheme and consulting with those who would be affected."
If the plans are agreed by councillors at a meeting on 10 November, a consultation will begin with the results considered in the new year.
Several other councils in Wales, including Swansea, Carmarthenshire and Flintshire have already approved plans to suspend the scheme.


Firmus Energy is putting up gas prices by more than 12% from the end of March.

The company supplies about 50,000 customers in the greater Belfast area and a further 30,000 beyond Belfast.
The price increase means a typical household customer will see bills rise by £61 a year.
Last week, the other major gas supplier in Northern Ireland, SSE Airtricity, announced it was putting up prices by more than 7%.
Firmus Energy said the move reflects the "rising natural gas commodity market" - which has seen wholesale prices in the UK go up by more than 50% over the last 12 months.
Managing director Michael Scott said: "We understand the importance of price stability for customers and apologise for having to increase prices.
"Over the past three years we have been able to reduce or maintain our prices."
The price rise follows consultation with the Utility Regulator, the independent government department responsible for regulating the electricity, gas, water and sewerage industries in Northern Ireland.
It will come into effect for Belfast customers from 7 April and for non-Belfast customers from 31 March.
Kevin Shiels, from the Utility Regulator, told Good Morning Ulster that it was "satisfied" that Firmus were justified in raising gas prices.
"To put it into some context, this is the first rise in three years and actually in two of the last three years there have been price falls.
"It is unwelcome, of course, but it is reflective of underlying costs and we're satisfied that it is justified."
He added that overall gas prices are "below the levels seen in the Republic of Ireland and on a par with levels in Great Britain".
"So, gas customers in Northern Ireland can be satisfied that the regulator is protecting them and ensuring prices are being kept as low as possible."


A sympathetic ear - and voice - is behind a contact centre firm's decision to open its new funeral planning business in south Wales.

Carpeo is hoping to create 300 jobs within five years in Newport, which beat off competition from Teesside.
One major factor was the "consoling" and "empathetic" Welsh accent which, the company said, was important for its market.
It hopes to recruit the first 24 staff to start work next month.
The company, which already employs 250 people in Swindon, is expanding and aims to have 60 people working at its new Carpeo Estates Planning offices in Cleppa Park by the end of the year.
It has been supported by a £500,000 Welsh Government grant based on the number of jobs created.
Account managers will be on £22,000 basic starting salaries.
The business has also teamed up with a legal firm to arrange affordable wills.
Carpeo Estate Planning's chief executive Mike Minahan said: "The quality of people available and their experience of working in a regulated services market is a huge pull.
"On the softer side, the Welsh accent is sympathetic and consoling, particularly important in our market."
Dr Mercedes Durham, a senior lecturer of sociolinguistics at Cardiff University, has studied the Welsh accent and found it was perceived as "funny". But she said: "It's also a friendly accent so that is possibly what people would hope to listen to at a time like that."
32,000
workers
10,000 number of workers in 1999
250 contact centres, from the AA to Zip World
£650m  value to Welsh economy
Q&A: Sandra Busby, managing director of the Welsh Call Centre Forum
How strong is the sector in Wales at the moment?
It's very strong. We just represent people in the contact centre side, not the total business - so Admiral have 5,500 people in Wales and 4,700 are in the contact centre.
"We call them contact centres not call centres now because there are multi-channels - people will host web chats, answer phones, emails and, increasingly, look after social media. It's about customer contact.
The sector has changed considerably since 1999. That's due to technology - an example of that is the DVLA which pushed people into self-serving online. The same with booking cinema tickets or paying the bank's credit card bills. You might have expected to see a reduction but we've seen a growth in jobs.
What parts of the UK and abroad is Wales competing with for jobs?
Northern Ireland and the North of England; South Africa, eastern Europe and India.
South Wales is pretty established now as a call centre location. What are the particular attributes its workers offer? What do employers like?
Wales is well placed on competitive salaries, building costs and support from Welsh Government. Staff turnover tends to be lower, a more loyal workforce. When you look at the right behaviours to go with the skills - people turn up for work, they want a career and to progress.
There are some who still say call centre jobs are not 'real' jobs.
In 1999, there were team leaders who are now senior managers. People move up the ranks. Working in customer contact can involve sales, marketing, customer service, a whole variety of jobs and working for some great brands - Barclays, Virgin, HSBC, PPI and cold calling damaged the industry.
Prof Martin Rhisiart, a business strategy expert at the University of South Wales, said computerisation was predicted to have an effect - and this could impact on the traditional call centre.
"We may well be at peak levels. Many leading experts in artificial intelligence and machine learning are themselves surprised by the pace of acceleration and we are at that exciting point where things might happen relatively quickly over the next five or 10 years. We might see entire industries change and entire working patterns change."
Economy Secretary Ken Skates said: "Carpeo has ambitious growth plans with the potential for further future investment in Wales and I welcome their plan to open this new business in Newport that will create a range of jobs and training opportunities for local people."
A spokesman for the Welsh Conservatives said: "Any new jobs in Wales are to be welcomed, and it's further evidence that the UK economy is performing positively under a Conservative government that the company is seeking to create new posts.
Plaid Cymru's economy spokesman Adam Price said it was good news to see jobs created in south east Wales but the Welsh Government continued to "fail the rest of the country".  He added: "Important parts of Wales like the valleys, rural Wales, the west and the north of Wales are not getting their fair share of investment."
The Wales Green Party said it was hoping that Carpeo would be the company "to buck the trend of zero hours contracts and pressurised conditions which workers have been subjected to in other call centres".


A car salesman has received a flood of congratulatory tweets after he was mistaken for an Olympic gold medallist.

Jason Kenny, 46, has been getting more than 50 messages a day on Twitter from fans of his namesake who has won three gold medals in Rio.
The father-of-one, who like the Olympian is originally from Farnworth, said it was an "absolute pleasure" to get the cyclist's tweets.
"I reply and say thank you but I am not in Rio", he told the Bolton News.
The Peugeot car sales manager, who lives in Adlington, said it was no trouble for him and "because he's such a nice guy, they are always very nice messages".
Mr Kenny has gone to considerable efforts in his Twitter biography to differentiate himself from the star.
It reads: "Bolton lad but not an Olympian, that's @jasonkenny107 who's amazing + not Canadian that's @jkenney who's...Canadian. Often confused for both you ain't the first."
Cyclist Jason Kenny equalled Sir Chris Hoy's British record of winning six Olympic gold medals on a sensational night in Rio on Tuesday.
Mr Kenny then woke up to a string of tweets praising the 28-year-old Olympian for his success.
He said it has happened for years, starting during the Beijing games, continuing in London and now Rio.
"I usually just re-tweet them or sometimes I reply", he said.
People "usually apologise" when they realise their mistake, he said, "but they don't need to - it's easily done!"
A keen cyclist himself, Mr Kenny remembers getting a "good luck" tweet from the Olympian in 2012 when he messaged him about a bike challenge he was completing early one Sunday morning.
He said the sportsman "is doing fantastically" in his career, adding: "If he does not become Sir Jason Kenny, then there is something wrong."


We know that Germanwings Flight 4U 9525 was flown into a mountain by co-pilot Andreas Lubitz, 27, after he locked the plane's pilot out of the cockpit.

A German criminal investigation into the crash concluded in January that Lubitz bore sole responsibility for crashing the jet.
The final accident report by the French authorities answered many questions - but some are still a mystery.
Investigators ruled out terrorism early on and their position did not change when it was revealed that they believed Lubitz had deliberately crashed the aircraft.
That was upheld in the final report, which found that he had been suffering from psychiatric issues he had hidden from his colleagues.
The co-pilot did not behave in a peculiar or extreme manner and people who knew him expressed shock over the event.
"He's not the type of guy who would try and kill other people - absolutely not," a neighbour said.
"He was really just a very normal, not very remarkable, nice young man," said Klaus Radke, the president of the club near Montabaur in Germany where Lubitz had learned to fly.
Lubitz had battled depression before, suspending his training for medical reasons in 2008.
The final crash investigation report detailed his medical history and showed he had started to suffer from a "severe depressive episode without psychotic symptoms".
During that period, he considered suicide and "made several 'no suicide pacts' with his treating psychiatrist and was hospitalised", the report says.
In April 2009, his medical certificate was not revalidated "due to depression and the taking of medication to treat it".
In July that year, he was declared "entirely healthy" and given a one-year medical certificate, with a note that it must be renewed each year.
It was renewed annually without incident until December 2014.
It was then that Lubitz consulted doctors about "vision problems and sleep disorders" but eye specialists could not find a physical cause.
Instead, investigators say, he was diagnosed with a "psychosomatic disorder" - a physical illness caused by a mental factor.
In February 2015, he was given a sick certificate for eight days, which he did not forward to the airline.
Over the next month, he would be issued several more medical certificates, none of which his employer saw; was prescribed insomnia and antidepressant medication; and was referred "for psychiatric hospital treatment due to a possible psychosis".
Traces of the medications were found in his remains during a post-mortem toxicology exam.
"On the day of the accident, the pilot was still suffering from a psychiatric disorder, which was possibly a psychotic depressive episode, and was taking psychotropic medication," the report found.
"This made him unfit to fly."
Prosecutors in Duesseldorf at the time of the crash found torn-up sick notes, including for the day of the crash.
In April 2015, German prosecutors said Lubitz had researched "ways to commit suicide" on his tablet at home in the week before the crash. Another of his internet searches was for "cockpit doors and their security provisions".
The German tabloid paper Bild said (in German) it had seen documents that said he was suffering from a "personal life crisis", having recently broken up with a girlfriend.
But even when we have a fuller picture of Lubitz's state of mind before the crash, some of his actions may remain a mystery forever.
For example, after he had decided to kill himself and everyone else on board the plane, why did he set the aircraft on a controlled, rather than a sudden, descent?
Depression is a serious illness, and it affects everyone differently. People experiencing depression can reach such a state of alienation that they risk taking their lives - but the vast majority of people with depression would never harm anyone other than themselves.
Writing in the Times, Jennifer Wild, a psychologist at the University of Oxford, has said that the irrational thinking evident from Lubitz's actions in the cockpit may have been triggered by depression, possibly caused by a recent traumatic episode. "Perhaps in his state he did not consider the consequences of his actions, or perhaps he did not care because he was consumed with ending his life," she wrote, adding that drug-taking or a bout of extreme anger might also explain his actions.
The black box recording of Lubitz's calm breathing as he pressed the controls to send the aeroplane hurtling to the ground may lead some to believe he was a psychopath but Dr Wild notes that psychopaths generally avoid harming themselves.
Sir Simon Wessely, president of the Royal College of Psychiatrists, said that millions of people in Britain suffered from depression, which is a treatable illness. He told the BBC that this included pilots who "resume flying, perfectly safely, for maybe tens of years afterwards".
The fact that Lubitz appears to have been signed off as sick raises the question of whether there was - or should have been - contact between his doctors and the airline.
Medical practitioners take an oath to maintain patient confidentiality but some US states have expanded doctors' duty of care to the community at large. This allows them to warn third parties if they think it necessary.
In Germany, trainee pilots are subjected to medical examinations which include oral psychological assessments. There is some debate as to whether such assessments are thorough enough. One question an examiner might ask a pilot is, "Do you have a butterfly collection at home?", the Suddeitsche Zeitung reported (in German).
At the time of the crash, Lufthansa said that after they hired pilots they did not subject them to regular psychological examinations. This is obligatory in other countries, such as the US and UK.
Airline staff are encouraged to report strange behaviour on the part of their colleagues but a former pilot told the BBC that peer pressure could act as a brake on this process. And Carsten Spohr, Lufthansa's chief, admitted: "All the safety nets we are all so proud of here have not worked in this case."
But Mr Spohr also said: "No matter your safety regulations, no matter how high you set the bar, and we have incredibly high standards, there is no way to rule out such an event. This is an awful one-off event."
Aircraft-assisted pilot suicides are rare. A 2014 study by the Federal Aviation Authority identified eight such instances in the US between 2003 and 2012, accounting for 0.29% of all fatal aviation aircraft accidents. All the pilots involved had been medically screened and none had demonstrated mental disorder, depression or suicidal thoughts.
Some people are asking why there is no system for wresting control of a plane from a control tower. In fact, such a system does exist, reports the Daily Mail, but it is not being used. In 2006, Boeing was awarded a patent for an "uninterrupted autopilot system" with its own power supply that could be activated by those on board a plane or on the ground. However, safety concerns - including the possibility that such a system could be hacked - have prevented its roll-out.
The crash also raises questions about the cockpit door mechanism which Lubitz used to keep the pilot out. The system, which allows a pilot to override the coded entry mechanism on the outside of the door, was designed in the event of a terrorist emergency.
Airlines are going to have to balance those concerns against the possibility that individuals like Lubitz might decide to do harm, said the BBC's transport correspondent Richard Westcott.
Lubitz was able to fly the plane into the ground without interruption since he seized the opportunity to lock the cockpit doors while the plane's pilot was going to the toilet.
Some airlines enforce a "rule of two" - that there should never be fewer than two people left in the cockpit. For these airlines, a member of the cabin crew enters the cockpit when appropriate to ensure this rule is followed.
After the Germanwings crash, several airlines, including Lufthansa, announced they were adopting this rule.
The European Aviation Safety Agency has recommended that at least two people be present in the cockpit at all times. China's aviation authority has also introduced the rule and the UK's Civil Aviation Authority has contacted all UK airlines "to require them to review all relevant procedures".
What relatives of plane crash victims need most are answers, experts say. But the more we learn about Lubitz, the more heartbreaking the Germanwings crash seems.
Evidence from research suggests that trauma inflicted by other humans on purpose is more difficult to come to terms with than natural disasters, clinical psychologist Roderick Orner told the BBC.
Acts of violence are also harder to process than accidents due to negligence or mechanical failure. "Violence is often experienced as an attack on human integrity," says psychiatrist Lars Weiseth. "This aspect causes increasing anger, loss of trust in companies and people, and sharply increases the risk to mental health."
The fact that Lubitz seemingly had no agenda for his actions does not necessarily make things easier, since the deaths could seem meaningless. If he had been a terrorist, Prof Weiseth says, relatives might be able to see their family members as "involuntary participants in an important struggle for democratic values".


Great Britain's Jade Jones retained her Olympic taekwondo title - winning GB's 22nd gold of the 2016 Games.

The 23-year-old won a thrilling final 16-7 to defeat Spain's Eva Calvo Gomez in the -57kg category in Rio.
Two head kicks in the third round sealed victory for Jones - who has now won both GB's taekwondo golds since its introduction as a medal sport in 2000.
"I'm still young so to be double Olympic champion already is crazy to be honest," she told BBC Sport.
"I started crying before the semi-final because I was just so nervous and felt so much pressure. But I pulled it off when it mattered so I'm just so happy.
"I obviously knew I'd feel some pressure as the reigning Olympic champion but I didn't realise how much it would be.
"The support has been amazing here and I just want to thank everyone. It means the absolute world to win again."
Her success means Welsh athletes have now contributed 10 medals, including four golds, at the Rio Games.
Sailor Hannah Mills and cyclists Owain Doull and Elinor Barker have also won gold in what has been a record medal haul for Wales.
Jones won at London 2012 to claim GB's first Olympic gold medal in the sport and is the current European champion.
The top-ranked Briton had to battle through four fights on Thursday to retain her Olympic crown.
She comfortably saw off Morocco's Naima Bakkal with a 12-4 victory before a 7-2 success against Raheleh Asemani of Belgium in the quarter-finals.
Her dominance continued with a 9-4 success over Sweden's Nikita Glasnovic in the semi-final to set up a fight against world number two Calvo Gomez.
Jones took a 6-0 lead in the first round with two head kicks to exert her authority on the contest.
The Spaniard fought back in the second round to close to 7-6.
The pair traded cut kicks at the start of the final round before Jones connected with two head kicks in quick succession to secure gold.
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A fisherman who almost killed a man for trying to defuse an argument between him and a woman in a bar on Islay has been remanded in custody.

Andrew MacGillivray, 33, punched Keith Cameron and stood on his chest, causing his ribs to crack, near the Ardview Inn, Port Ellen, on 23 March last year.
He admitted assaulting the 41 year old to the danger of his life.
The High Court in Glasgow heard Mr Cameron was fortunate to be alive. Sentence on MacGillivray was deferred.
The court heard that MacGillivray got into an argument with a woman in the bar and Mr Cameron stepped in to try and calm him down.
MacGillivray was asked to leave the pub but waited nearby for Mr Cameron to leave.
When he spotted the victim, he knocked Mr Cameron down with a punch before battering him as he lay on the ground and standing on his ribs.
Mr Cameron - who is known locally as Cabana - was later spotted by a passing couple who knew him but they were unable to recognise him due to his injuries.
As an ambulance took Mr Cameron to hospital, MacGillivray returned home and told his wife: "I think I've killed Cabana. I hope he's OK. I know I hurt his ribs."
He insisted Mr Cameron had a "go" at him in the bar before MacGillivray later assaulted him.
The father-of-three said he stood on Mr Cameron's ribs, heard them crack and the victim's chest "went as flat as his stomach".
Police later arrested MacGillivray but, before being held, he told his father-in-law: "I did it - I would do it again and worse. If you want to be hard, you have to act hard."
Mr Cameron had injuries to his face, eye and significant fractures to his chest. He was eventually flown to the Southern General Hospital in Glasgow for treatment.
A doctor said the injuries to the chest were more commonly found when a heavy object falls onto a person.
The medic added Mr Cameron's life had been at threat and that he was "fortunate to be alive".


A court in America has decided that this monkey doesn't legally own the photo that she took of herself.

This macaque monkey won world-wide fame in 2011, when she got hold of a photographer's equipment, and took her own selfie.
But it led to a row over who owned the photograph.
Knowing who owns the photo is important, because it affects copyright.
Copyright protects the photo under law, so that people can't use it without the owner's permission.
Some people said that they could use the picture without anyone's permission, because it was taken by a monkey - not a person.
But the photographer, David Slater, argued that the photo was his, because it was his equipment.
Now an American Judge has decided that the monkey doesn't own the photograph.
Even though animals are protected by the law like people are, he said that it doesn't mean that they can own things under the law as well.


There are at least 46,000 Twitter accounts operating on behalf of Islamic State (IS), a new US study claims.

The actual number, identified in the final three months of 2014, is probably much higher, says the report, co-authored by the Brookings Institution.
It said typical IS supporters were located within the militants' territories in Iraq and Syria.
Three-quarters of them tweet in Arabic and about one-in-five use English. They have on average about 1,000 followers.
Islamic State has become well known for its use of social media, especially Twitter, to propagate its message.
The study, called The Isis Twitter Census, was written by JM Berger of Brookings and Jonathon Morgan, a technologist.
Jihadists will exploit any kind of technology that will work to their advantage, said Mr Berger, but IS is much more successful than other groups.
Most of these IS accounts were created in 2014, suggesting that the numbers are climbing very steeply, despite more than 1,000 IS-related accounts being shut down by Twitter in the final months of 2014.
Mr Berger's report put a maximum estimate of pro-IS accounts at 90,000 but concluded that the "best" estimate was 46,000.
Even that lower figure would put their reach into the millions, said Aaron Zelin, an expert on jihadist groups, and a fellow of the Washington Institute.
But it would also include multiple accounts held by any one individual, he warned, a practice aimed at combating account terminations.
The top Twitter feeds associated with Islamic State, he said, would disseminate the message of those at the top - the military operations, the organisation's activities and videos featuring everyday life under IS rule.
Below that, said Mr Zelin, you have people who are not directly connected to IS but who retweet its communications.
What you don't often find, he says, is evidence of direct recruitment of fighters.
"Recruitment is not overt on Twitter. Most of that happens on applications like Kik, WhatsApp and Skype, which are peer-to-peer. What they are doing publicly on Twitter is to draw people in."
Twitter can sometimes be used as an initial means of contact between a radicalised person and someone who could recruit them, says Mr Zelin, but the conversation would very quickly migrate to direct messages or other platforms.
Islamic State, he notes, has made social media a central part of its strategy, and the age of its supporters coincides directly with the young demographic that uses social media.
The threat of these new technologies in the hands of IS was this week underlined by the new US Pentagon chief, Ashton Carter.
"This is a social media-fuelled terrorism group in a way we haven't seen yet," he told senators in Washington.
"People who are very distant from any battlefield, from any experience of radicalism, are suddenly becoming enticed through social media."
Thousands of foreign fighters have joined the battlefields of Iraq and Syria, mostly from neighbouring countries in the Middle East.


A former police headquarters in Glasgow is being put up for sale.

The 190,000 sq ft Pitt Street site was vacated recently by Police Scotland, which has relocated to new administrative headquarters in Dalmarnock.
The site was built in 1924 and used by the Scottish College of Commerce before being taken over by the then Strathclyde Police in 1975.
It is expected to be demolished to allow for new development.
Mandy Watson, from property agents Ryden, said: "This is an exciting and rare opportunity and we look forward to bringing the property to the market.
"The site is well connected and would suit a whole range of uses."
Deputy Chief Constable Neil Richardson from Police Scotland said. "This represents a significant milestone for Police Scotland as we move to a purpose-built facility in Dalmarnock that will support the regeneration of that local area.
"Pitt Street served the legacy Strathclyde force well for many years, occupying an enviable location in the heart of the city.
"We look forward to seeing that site being developed again for the benefit of the city."


A prisoner who was said to have escaped to Spain has been rearrested near Nottingham, police have said.

Haroon Ahmed, 26, from Derby, has been on the run since leaving HMP Dovegate in Staffordshire on Wednesday.
Ahmed, who was serving a sentence for a robbery he committed in 2008, reportedly fled to Spain.
Serco, which runs the prison, said it had commissioned an "urgent investigation" into the circumstances of Ahmed's escape.
Staffordshire Police said it could not confirm or deny he had left the UK after the Sunday Mirror claimed to have tracked Ahmed down in Marbella.
His brother, Majeed Ahmed, 25, of Clarence Road in Derby, has been charged with assisting a prisoner in escaping from prison.
Michael Guy, Serco's director at HMP Dovegate, said: "I have commissioned an urgent investigation into the circumstances of the escape.
"We are working closely with the police to identify what went wrong and to address any failings."


Angola have appointed Brazil's Roberto Bianchi as their new coach, the football federation said on Wednesday.

The 50-year-old, who has previously worked in Jordan, Spain, Montenegro and Indonesia replaces Jose Kilamba, who had been coaching Angola since 2015.
Bianchi, the fourth Brazilian to coach Angola, has been coach of Angolan club Petro de Luanda since last year.
"We have a huge challenge to qualify for the 2019 Africa Cup of Nations," Bianchi said.
Qualifying for the tournament in Cameroon will start in June, and Angola will face Burkina Faso, Botswana and Mauritania in their group.
Angola reached the Nations Cup quarter-finals in 2008 and 2010 and also qualified for the 2006 World Cup.
But they have failed to qualify for the last two Nations Cups and are already out of the running for 2018 World Cup, eliminated by South Africa.
The Palancas Negras (black antelopes) are ranked 45th out of 54 countries in Africa and 148th in the world.
"My mission is also to improve the country's position in the Fifa rankings," added Bianchi.


A 39-year-old man, whose solicitor claimed has the biggest criminal record in British and Irish judicial history, has been jailed.

Eamon Lynch, 39, from Wesley Street in Derry admitted a series of road traffic offences in the city in 2010.
The father-of-eight's criminal record now stands at 472 convictions, including almost 300 driving offences.
At Londonderry Crown Court, Lynch was given a 28-month prison sentence, half of which he will serve in custody.
He also has previous multiple convictions for burglary, assault, forgery and drugs offences.
Judge Piers Grant said Lynch's record was "appalling" and contained the most significant number of convictions ever to come before him.
On Wednesday, the court was told Lynch was seen driving a car that struck two parked cars, two years ago. The owner of one of the cars recognised him. Lynch ran off and was later seen walking across Craigavon Bridge by the police.
As they approached him, he threw a set of keys into the River Foyle.
He was arrested and when breathalysed was found to be more than twice the legal limit. At the time he had been disqualified from driving until 2023.
The court was told Lynch absconded from Northern Ireland to live in Donegal last year where he committed seven further road traffic offences.
Judge Grant imposed a 28-month jail sentence and told Lynch he would serve 14 months in custody and would be on licence for the other 14 months.


Hackers stole millions of social security numbers by cracking open the networks of large US data brokers, reveals an investigation.

The ID details of US First Lady Michelle Obama and many other famous people were exposed by the hack attack.
Journalist Brian Krebs tracked the information back to hackers who ran an online market for confidential data.
He found they got their data by compromising computers sitting on the data brokers' corporate networks.
In March, Krebs, as well as the FBI and US Secret Service, started looking into how the exposed.su website was getting hold of social security numbers and other details of many famous Americans.
The mysterious website, which has now been closed down, published confidential information about Bill Gates, Beyonce Knowles, Jay-Z, Ashton Kutcher and many others.
The investigation into exposed.su showed it had bought its information from another site, called SSNDOB, that advertised itself as a market for just such private data. SSNDOB sold data records on individuals for as little as 50 cents (30p). The records of about four million Americans seem to have been accessed via the data-selling site.
In early summer, wrote Krebs in a blogpost, SSNDOB had itself been attacked and its database stolen, copied and widely shared.
Analysis of the SSNDOB database by Krebs and forensic computer expert Alex Holden, of Hold Security, revealed the ID data being sold had come from machines sitting on the internal networks of several American information aggregation firms. Compromised computers or systems at LexisNexis, Dun & Bradstreet and Kroll were all named by Krebs as the sources of the data.
In the commercial world, the three firms are well known for providing businesses with data about potential commercial partners and customers. The open access the hackers enjoyed meant they could run their own queries about individuals via the databases of the three firms.
"All three victim companies said they are working with federal authorities and third-party forensics firms in the early stages of determining how far the breaches extend," wrote Krebs on his blog.
LexisNexis issued a statement denying that its information was exposed.
"To date [we] have found no evidence that customer or consumer data were reached or retrieved," said the statement.
A spokeswoman for the FBI told Reuters it was investigating the breaches identified by Krebs but would give no more details.


Somalia's ban on Kenyan flights carrying the herbal stimulant khat has come into force, with no explanation as to why or how long it will be in place.

But the semi-autonomous region Puntland region is among some federal states defying the ban.
Khat is popular in Somalia but it is grown in Ethiopia and Kenya.
Hundreds of Kenyans, including farmers, could be affected by the decision, which has been criticised for coming without any warning.
BBC Somali Service editor Farhan Jimale says it is equivalent to a major city like London banning imports of alcohol overnight.
But as khat has to be taken fresh, there are no stockpiles.
Economic hit: Analysis by BBC Somali Service's Ahmed Adan
More than 15 cargo flights full of khat arrive in Somalia's capital, Mogadishu, every day from Kenya. According to Somali anti-khat campaigner Abukar Awale, they bring in about 12,000 bags of khat a day, which have a total retail value of $400,000 (Â£298,000).
Mr Awale, a former khat addict, argues that the stimulant contributes to domestic violence and other abuses.
The normally bustling Beerta khat market in Mogadishu has been practically deserted because of the suspension.
One khat seller in Mogadishu, Fartun Mohamed, told the BBC that her family's livelihood has been put in jeopardy because of the suspension as this was the only way she managed to feed her 10 children.
The planes from Kenya arrive in Somalia's capital, Mogadishu, in the morning and the leafy stimulant, which is not cheap, is usually chewed after lunch, mainly by men, in the afternoon and into the evening.
Civil Aviation Minister Ali Ahmed Jangali, who announced the ban on Monday, did not give a reason for the suspension, which is understood to be temporary.
He denied that it was because Somalia was hosting a meeting on Saturday for the regional body, Intergovernmental Authority on Development (Igad).
Workers at a khat-exporting company in Kenya's capital, Nairobi, were told not to report to work on Monday.
The Kenyan government has in the past pledged to support the growers of khat, which is also known as miraa in Kenya, after it was banned in much of Europe.
Khat is also banned in a number of other countries, including the US and Canada.
Source: Talk to Frank


Manchester City did not deserve their last-minute Champions League victory at Borussia Monchengladbach, says Blues manager Manuel Pellegrini.

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Sergio Aguero's penalty earned a 2-1 win, with keeper Joe Hart saving a penalty before the Germans took a 1-0 second-half lead.
Nicolas Otamendi scored the equaliser as City recovered from the 2-1 loss to Juventus in their opening Group D game.
"We had a bit of luck to win the game," said the 62-year-old Chilean.
City had been beaten in three of their four previous matches in all competitions, including Premier League losses to West Ham and Tottenham as well as the defeat by the Italian champions.
"Against Juventus and West Ham we didn't deserve to lose and maybe today we didn't deserve to win but we did," added Pellegrini.
But the victory - only the third in their past 12 Champions League matches - boosted their hopes of reaching the knockout stage for a third successive season under Pellegrini.
City remain third in the group after two matches, level on three points with Spanish side Sevilla and three adrift of Juve.
England international Hart said his team were below their best against Monchengladbach, but disagreed with his manager about the final result.
"We were disjointed as we had been in the last few games, but we deserved to win," said the 28-year-old.
"We had some really good chances. It may have come late but Sergio Aguero is a cool guy and he will score.
"They've got some good movement - Kevin de Bruyne warned us about them. They've a very fit team and they work themselves into the ground.
"We profited when they were a little bit tired at the end. They made a few mistakes and we kept our quality."
Now Pellegrini hopes his squad - who were missing defender and captain Vincent Kompany through injury and saw midfielder Yaya Toure taken off at half-time - can get through to the international break without picking up any more knocks.
His players will link up with their national squads after Saturday's home league match against Newcastle.
"We need the international break because we have eight injured players and we don't have many options," he added.
"It is important for the players to beat Newcastle on Saturday and then after that we have 15 days."


Imagine waking up to this amazing view outside your window...

8 February 2015 Last updated at 10:44 GMT
The lucky astronauts on board the International Space Station have caught the Northern Lights touching sunrise over Earth.
US space agency Nasa released the stunning clip, with the quote from astronaut Butch Wilmore: "#Sunrise touches #Aurora. All we need now are angels singing."
The Northern Lights, or Aurora Borealis, are caused by the interaction of the solar wind (charged particles escaping the Sun) with the Earth's magnetic field and atmosphere.
Pictures courtesty of Nasa.


Presents are stacked round a huge gift wrapping machine in the centre of the room and there's a palpable air of excitement, mostly from the adults.

It's early November and in what has now become something of a toy industry institution, St Mary's Church in central London is playing host to the unveiling of the Dream Toys Top 12 list.
The dozen items represent the Toy Retailers Association's pick of what they think will be the most coveted items this Christmas.
Lego's Star Wars Rebel U-Wing Fighter features, as does a Thomas and Friends train set from Mattel, but self-styled "toyologist" Peter Jenkinson says that not everyone's Christmas purchases will be geared towards film and TV shows.
"There's a big demand for craft items and STEMS - science, technology, engineering, and mathematics."
He adds that small, pocket-friendly collectable lines such as Shopkins grocery characters, should fly off the shelves.
"Kids want something they can compare and share with friends."
The collectables trend could give the toy market a boost according to Gary Grant, chairman of the Toy Retailers Association,
"They bring people back out on to the high street because although people only tend to spend a small amount of money on a few pieces to add to a set, they do so on a regular basis."
Toy sales have been healthy in 2016, in fact the industry is on track for its best-ever year, says analyst Frederique Tutt, of market research firm NPD Group.
"We're expecting annual sales to reach 400 million toys for the first time, which will potentially see the industry going over the £3.3bn mark," she says.
As well as collectables, more traditional toys have been selling well, she says.
"Board games are the fastest growing segment this year, with sales up around 15% on last year."
However, sterling is about 18% weaker against the dollar than it was before the UK's vote to leave the EU, and this is likely to have an impact on the prices consumers pay for toys.
Andrew Dobbie, managing director of toy industry consultants Gameplan Europe, says that if sterling continues to trade at its current lower levels, there could be price increases in 2017 - but it won't affect firms in the same way.
"Big companies hedge up to a year in advance, so that they know what they'll be paying for the next 12 months. If a manufacturer has hedged all their projected purchases they could theoretically hold prices.
"If they haven't hedged it will be a different story. The next time a retailer has a purchase order, for example from the Far East where prices are in dollars, they could end up paying a lot more than before."
Retailers would then have the choice of passing on the cost or absorbing it. But Gary Grant doesn't think consumers will bear the whole brunt of a weak pound.
"If sterling is devalued by 18% we'll see a rise in prices, but not necessarily by the full amount. I think 5%-10% is more realistic."
James Murden, the co-founder of Mardles, a firm that manufactures and sells augmented reality stickers and colouring books, says the Brexit effect has been mixed.
"We have production bases in the UK and China. When we get large bulk orders, we have them made up in China. For UK orders and smaller international orders, we print in Bedfordshire and assemble the product in Bristol.
"Anything we have manufactured in Asia is costing more because we're paying in dollars. On the flip side, our product is cheaper for our overseas customers who are paying us in euros and dollars."
Source: Toy Retailers Association
Craig Wilkins, the marketing director of toy giant Hasbro, owner of brands such as My Little Pony, Trivial Pursuit and the Nerf Blaster, is cautiously optimistic.
"Toys are the last thing that parents cut back on when money's tight; kids always want to play and that's not going to change.
"We really have to focus on value for money, because whether a toy is a big or small ticket item, people will still pay if they think they're getting good value."
The UK's Brexit vote may not have an immediate impact on toy prices but Gary Grant says that there's another side effect of a weaker pound - there might not be enough seasonal staff to cope with demand,
"We definitely have a challenge; a lot of temporary staff in warehouses, shops and internet packing sites are from Eastern Europe. Employment agencies that I deal with are saying that people don't want to come to the UK for work.
"This could be down to the fact that potential employees from Poland, for example, are getting fewer euros to the pound."
It may be a topsy turvy time in Toyland, but in central London, as the Christmas carols waft from the speakers in the church hall, there are certainly more smiles than frowns. For now at least.


Police investigating the discovery of a man's body at a property in Dundee have said his death is not being treated as suspicious.

The body of the 42-year-old was found in Gleneagles Street at about 14:30 on Tuesday.
Officers were initially treating his death as unexplained.
But they confirmed on Wednesday afternoon that there were no suspicious circumstances.
As with all sudden deaths, a report will be sent to the procurator fiscal.


A 16-year-old girl was raped in a park in East Dunbartonshire on Sunday evening, police have said.

Officers said the girl was attacked in Westerton Park, Bearsden, at about 18:30.
Police Scotland said they were "following a positive line of inquiry".
A spokeswoman said: "We can confirm that officers are continuing inquiries after a 16-year-old girl was seriously sexually assaulted on Sunday within Westerton Park, Bearsden."


The history of a former industrial valley that is now part of a Surrey beauty spot is to be explored after £92,000 was awarded to the project.

The Surrey Hills Board will use the lottery  funds to rediscover the Tillingbourne Valley's heritage, chairwoman Christine Howard said.
She said the Tillingbourne used to have a gunpowder mill and was once one of the UK's most industrialised rivers.
Ms Howard said it was now home to dormice and a "sleepy little hollow".
"This is an opportunity for us to peel back and rediscover what the ancestors in this area got up to," she said.
The water power of the Tillingbourne river also used to support the leather, paper, iron and corn milling industries, and memories and knowledge of this history were fading fast, she added.
The valley includes the villages of Shalford, Chilworth, Albury, Shere, Gomshall, Abinger and Wotton.
Volunteers are being sought to help with the project, which will see a permanent exhibition created at Shere Museum.


The government has pledged billions for new free schools while existing school buildings in England are deteriorating, says the official spending watchdog.

Repairing all school buildings to a satisfactory standard will cost an estimated £6.7bn, according to a National Audit Office report.
Under government plans 833 free schools will open by 2021, costing £9.7bn.
The government said free schools were a vital part of meeting demand for new school places.
But shadow education secretary Angela Rayner said the policy continued "to waste millions opening free schools in areas that do not need them".
And Meg Hillier, chairwoman of the Commons Public Accounts Committee, said it was "taxpayers' money that could be used to fund much-needed improvements in thousands of existing school buildings".
Deteriorating school buildings are a "significant risk to long-term value for money", the report found.
Much of the school estate is more than 40 years old with 60% built before 1976 and the cost of repairs is expected to rise, with common defects including electrics and external walls.
Meanwhile, demographic changes mean the Department for Education will need to provide 420,000 more school places by 2021, researchers found.
Under government plans, about 270,000 of these new places will be in free schools, run by independent groups but funded by central government.
The free schools programme has been "much larger, in scale and cost, than the department initially planned", said researchers, noting that:
Free school places cost more than those in local authority schools - 50% more for secondary places and 33% more at primary level, said the report.
Under the government's current school building programme, construction costs are about the same for all types of school.
The higher cost of free schools "is mainly because free schools tend to involve the purchase of land", with the government expecting to spend £2.5bn on land between 2016 and 2022, the researchers noted.
"This level of investment would put it in the same spending bracket as the top five homebuilders in the UK."
The report also raised concerns that while free schools play an increasingly important role in addressing school places shortages, they create spare capacity when set up in areas that already have enough places.
Unfilled places mean schools lose funding, possibly harming their financial viability, said the report.
According to the report, spare places in 52 free schools which opened in 2015 could have a moderate-to-high impact on funding in 282 other schools.
Toby Young, director of the New Schools Network which represents free schools, said the report recognised that they were better value than previous school building programmes.
"They are the most cost-effective way to create the 750,000 new school places we need between now and 2025," he said.
The report noted that the government created 599,000 new school places in the five years to 2015 but pupil numbers continue to grow with demand shifting to secondary schools.
A Department for Education spokesman said more than three-quarters of free schools had been approved in areas where there was demand for new places and the vast majority were rated good or outstanding by Ofsted.
"The government is making a huge investment in the school estate of £23bn up to 2021, to create a further 600,000 new school places, deliver 500 new free schools, and rebuild and refurbish buildings at over 500 schools," the spokesman added.


Journalist Sue Lloyd-Roberts, who has an aggressive form of leukaemia, has said she has found a stem-cell donor.

It comes after a public appeal to find a donor for the BBC journalist, who has acute myeloid leukaemia and is dependant on a transplant to survive.
She posted on Twitter to say the donor was a "good match" and she would return to hospital in two weeks to undergo the transplant procedure.
"Thanks so much to all donors and all tweeted good wishes," she wrote.
Ms Lloyd-Roberts, who has also worked for ITN, has reported on events in Syria, Burma and North Korea among many others, and has campaigned for human rights.
The BBC held an open day last month for anyone aged 16-30 to join the register of the blood cancer charity Anthony Nolan Trust.
Since being diagnosed more than four months ago, Ms Lloyd-Roberts has undergone two rounds of chemotherapy at University College Hospital in London, and is now in remission.
She had expected a stem-cell transplant to take place in May, but the would-be donor failed medical tests and the operation was cancelled.
The Anthony Nolan Trust says that only one in about 1,200 people on the register ends up donating in any given year because matches are rare.


Twenty-nine South Africans have been charged with public violence amid the biggest student protests to hit the country since apartheid ended in 1994.

Police again fired stun grenades to disperse students in Cape Town, a day after protesters stormed the parliamentary complex.
Thousands also descended on the governing party's headquarters in the main city, Johannesburg.
The students are angry with a proposed increase in tuition fees.
Africa Live: BBC news updates
The demonstrations began last week at Johannesburg's prestigious University of the Witwatersrand, and have since spread to at least 10 universities, forcing the closure of many of them.
At the scene: Pumza Fihlani, BBC News, Johannesburg
On at least two occasions, police foiled attempts by the protesters to reach the headquarters of the governing African National Congress (ANC), pushing them back to their campuses. But the students regrouped and finally reached the building, named Luthuli House after South Africa's first Nobel Peace Prize laureate Albert Luthuli.
The students sang and chanted anti-apartheid songs, invoking memories of the decades-long campaign which led to the overthrow of the apartheid regime in 1994.
The ANC pulled out its election truck and seemed to be wiring a loud speaker, but the students refused to let the party's secretary-general Gwede Mantashe address them.
Instead, they gave him a memorandum outlining their demands.
"The honeymoon of 1994 - when we were told that we were free - is over," a student leader said in his address to the protesters.
Students said they would march on Friday to government buildings in the capital, Pretoria, to coincide with President Jacob Zuma's plan to meet protest leaders to discuss their grievances.
The mainly black students say they cannot afford fee increases and have rejected a government offer to cap increases at 6%, down from the 10% to 12% proposed by the management of universities.
The 29 people who appeared in court in Cape Town were not asked to plead.
The accused have been released from police custody, and the case postponed to February.
Those charged include the 63-year-old parent of a student at the University of Cape Town, the privately owned News24 site reports.
It published what was purportedly an official document, showing "high treason" was among the alleged offences for which he had been detained. However, the charge was not mentioned in court.
Correspondents say the protests show growing disillusionment with the ANC, which took power after minority rule ended in 1994, over high levels of poverty, unemployment and corruption in government.
Many black students say they come from poor families, and fee increases will rob them of the opportunity to continue studying.
Financially better-off white students have joined the protest, mainly to show solidarity with the black students.
In a statement, Mr Zuma said: "It is important that we work together to find solutions. Nobody disagrees with the message that students from poor households are facing financial difficulties and possible exclusion."
Correspondents say his intervention shows how seriously he is taking the protests.
Students are also demanding the resignation of Higher Education Minister Blade Nzimande, who said on Monday that the protests were not a national crisis.


Online retail giant Alibaba has again reported strong earnings, posting a 56% rise in quarterly revenue.

Net income grew by 94% to 14.7bn yuan ($2.2bn; Â£1.7bn;) for the three months ending June 30, compared to the same period last year.
The performance is in sharp contrast to US big box retailer Walmart, which posted a 23% drop in net income.
Analysts say the two results reflect both a global shift towards e-commerce and a broader shift towards Asia.
Investors have shown unbridled enthusiasm for Alibaba this year. The company's shares were up 5% on the results, and they are up 81% this year.
While these numbers seem almost unbelievable by US or European standards, some analysts think there's still plenty of room for growth.
"That's the challenge evaluating these companies because the market dynamics are so different than in the US and Europe," said Ben Cavender, from China Market Research Group.
He says e-commerce still only accounts for about 15% of the total retail market in China, so there's still plenty of untapped potential.
The news isn't all bad for the once-dominant retailer.
Store traffic is higher, but profits were down, in part because Walmart is spending money to keep pace with rival Amazon.
Walmart's US stores saw a 1.8% rise in sales compared with the second quarter of last year.
Still, its net income fell 23.2% to due to aggressive spending on e-commerce as well as costs of $788m connected to a one-time debt payment.
Both companies are in competition with US ecommerce giant Amazon, which has also seen significant growth in the last year.
But while Walmart is directly squaring off against Amazon, Alibaba's chief executive, Jack Ma, has made it clear that he's not relying on the US market for the company's growth.
And while Amazon has a presence in China, it hasn't made huge inroads.
"They don't have the funding, they don't have the brand recognition. They don't have the product that people want at the end of the day," said Mr Cavender.
On its home turf, Alibaba might be more worried about Walmart, which has a significant bricks-and-mortar presence, and has also formed an alliance with Alibaba's local rival JD.com
South East Asia, with its rapidly expanding middle class, is shaping up as the next battleground for global e-commerce giants.
"All of these players are looking at where the emerging spending growth is coming from," said Mr Cavender.
Amazon Prime has dipped its toes into South East Asia by setting up shop in Singapore.
Alibaba has opted for a different route by partnering with established local players.
In June, it invested a further $1bn in Singapore-based e-commerce platform Lazada Group, and on Thursday it revealed it had invested $1.1bn in Indonesia's Tokopedia.


The Nato military alliance has agreed to use surveillance planes in the fight against so-called Islamic State (IS) in Syria and Iraq, secretary-general Jens Stoltenberg says.

He says the aircraft will support the US-led coalition targeting the group.
Nato will also train Iraqi forces and support special forces in Tunisia, a major recruiting ground for IS.
Meanwhile, the alliance has agreed to keep troop levels in Afghanistan and reiterated a funding pledge, he adds.
Mr Stoltenberg made the remarks on the second day of the 28-country military alliance summit in Warsaw.
He said the surveillance agreement against IS, using Awacs surveillance planes, was a "clear signal of our resolve to help tackle terrorism".
Additionally, the alliance will start a training and capacity-building mission for Iraqi armed forces, a country Mr Stoltenberg says is central in the fight against the jihadist group.
Nato does not have many military resources of its own; they all belong to individual member countries.
But one of the few things that Nato does hold in common is a small fleet of Awacs - airborne warning and control aircraft - giant Boeing planes the size of an airliner with a rotating radar dish above the fuselage.
Nato's Awacs fleet is based at Geilenkirchen, in Germany, with 16 Boeing E-3A aircraft with multi-national crews. They are drawn from 15 of the alliance's members. There are forward operating bases in Greece, Italy and Turkey.
An Awacs typically cruises at some 30,000ft (9,144m) providing a radar picture over a vast area. It is expected that the new Nato mission against IS will begin in the autumn with the aircraft operating within Turkish airspace or in international airspace over the eastern Mediterranean.
Nato will also work to establish an intelligence centre in Tunisia and will support the country's special operation forces.
"We will provide greater support to our partners, so they can secure their countries and push back against violent extremism," Mr Stoltenberg said.
Co-operation with Jordan and Libya's new government would also increase, he added.
The alliance will also launch a new maritime operation in the Mediterranean, whose responsibilities will include counterterrorism.
The US-led alliance in Afghanistan costs about $5bn (Â£3.86bn) a year, with approximately $3.5bn (Â£2.7bn) coming from the US.
Nato is expected to contribute with $1bn (Â£770m), with the remaining funds due to come from the Afghan government.
"Afghanistan still faces serious instability and violence so our continued political, military and financial engagement is of great importance," he said.
Mr Stoltenberg added that Nato's troop levels in the country would be similar to this year, at around 12,000.
This comes after US President Barack Obama promised to slow a planned draw-down of US troops from Afghanistan.
The initial plan was to reduce US troop numbers from 9,800 to 5,500 by the end of the year, but now 8,400 will remain, Mr Obama has said.


Radioactive particles from nuclear tests that took place decades ago persist in the upper atmosphere, a study suggests.

Previously, scientists believed that nuclear debris found high above the Earth would now be negligible.
However this research shows that plutonium and caesium isotopes are still present at surprisingly high concentrations.
The work is published in the journal Nature Communications.
Lead author Dr Jose Corcho Alvarado, from the Institute of Radiation Physics at Lausanne University Hospital in Switzerland, said:  "Most of the radioactive particles are removed in the first few years after the explosion, but a fraction remains in the stratosphere for a few decades or even hundreds or thousands of years."
However, he said the levels were not high enough to pose a risk to human health.
Radioactive hangover
At the height of the Cold War, when the nuclear arms race was in full swing, weapons were being developed and tested around the world.
But more than 50 years on, their radioactive legacy remains.
While nuclear explosions initially throw material up into the air, scientists had thought that the radioactive particles would remain for a limited time.
In the troposphere (the lower layer of the atmosphere that sits directly above the Earth), the isotopes are removed fairly quickly, as they are "washed out" by attaching to rain or snow or are drawn down by gravity.
However, in the stratosphere (the layer that sits from about 10-50km above the Earth), the Swiss team believes that some particles become trapped.
"The concentrations we measured were in the order of about  1,000 to 1,500 levels higher in the stratosphere than in the troposphere," said Dr Jose Corcho Alvarado.
While the tests were carried out over Switzerland, the team said they expected similar levels would be found at the same latitude elsewhere around the world.
The scientists also found that this material can be moved around in the atmosphere by natural events such as volcanic eruptions.
For example, in 2010 after Iceland's EyjafjallajÃ¶kull volcano erupted, plutonium levels in the lower atmosphere increased.
While scientists say the long-term effects are not clear, the lead author Dr Jose Corcho Alvarado said:  "It is important to say that this is not  dangerous for the population."
He added that the nuclear debris could be tracked to find out more about how particles in the atmosphere move around.


Scientists have sequenced the complete genomes of two Tasmanian devils in the hope of finding clues to preserving this highly endangered marsupial.

Devil populations have been decimated by a highly contagious facial cancer that is transferred when these aggressive animals bite each other.
The findings will help researchers select the best individuals to be kept in captivity for eventual re-release.
The research is outlined in Proceedings of the National Academy of Sciences.
The Tasmanian devil, Sarcophilus harrisii, gets its name from its high-pitch, blood-curdling squeal, and is renowned for fighting over access to animal carcases, which it grinds with the bone-crushing force of its jaws.
In 1996, a wildlife photographer snapped an image of an animal in the far north-east of Tasmania with a peculiar growth on its face.
The growth, it turned out, was neither benign, nor isolated to this one individual, but was a highly contagious, fatal cancer that seemed to be spreading through the population at lightning speed.
By 2007, conservationists reported that Devil Facial Tumour Disease, DFTD, had wiped out more than 90% of devil populations in the north-east of Tasmania, and was spreading west.
A strategy to save the devil from extinction was begun.
Now, an international team of genomicists is offering a helping hand.
The researchers took advantage of the latest technology to read the genetic sequence of two devils - an uninfected male called Cedric, and an infected female called Spirit -  along with smaller segments of DNA from 175 other individuals.
The team hopes to use the genomes to pinpoint which individuals should be placed into "protective custody" to wait out the cancerous epidemic before being reintroduced.
From their analysis, the scientists predicted how best to capture as much genetic diversity among the individuals put aside for captive breeding, explained lead author Webb Miller, a genomicist from Pennsylvania State University, US.
He said that choosing individuals who were very genetically dissimilar should take priority over whether they were resistant to the cancer.
"It is a big step forward to actually get the genome sequence from this animal... the [world's largest] remaining carnivorous marsupial," said zoologist David Rollinson from the Natural History Museum, UK.
Getting two complete genomes was very valuable, said Dr Rollinson, but getting as many samples as they did, from as many different animals was "just the icing on the cake".
Dr Rollinson thinks that a similar approach could be used to study and save other endangered animals.
The researchers also sequenced one of the five tumours from Spirit's head for clues to why the Tasmanian devils fail to recognise the cancer as "non-self", and destroy it before it takes hold.
Understanding what it is about the devil's immune system that makes it so ineffectual at picking up the facial cancer will not only help treat those already infected, but will hold clues about whether the cancer can jump species.
"The greatest worry is that it will jump into another marsupial," said cancer geneticist Elizabeth Murchison from the Welcome Trust Sanger Institute in Hinxton, UK.


The public transport system is failing the oldest and most vulnerable in society in England, a report says.

The Future of Transport in an Ageing Society was compiled by think tank The International Longevity Centre - UK (ILC-UK) and charity Age UK.
It says millions of older people are faced with travel problems.
More than half of over-65s either never use public transport or use it less than once a month, despite being eligible for free bus travel, it says.
Age UK said the transport system was not currently meeting the needs of the growing ageing population.
The report also claims it is the oldest, those in poor health and those living in rural areas who are let down the most by public transport.
Its findings include:
The report calls for older people to be supported in driving for longer, with viable alternative transport options to be made available for those who are unable to drive.
And it says research by Age UK shows that health problems are more likely than age alone to lead to people giving up driving.
It claims only 1% of people aged 60 or older, who were surveyed by the charity, would give up driving because of their age, while 43% would stop driving due to health concerns.
Helen Creighton of ILC-UK said travel was essential for independent living, and had benefits for people's physical health and mental wellbeing in later life.
"This report, which highlights the travel difficulties facing older people, emphasises the need to adapt our transport system to meet the demands of our ageing society," she says.
Caroline Abrahams, charity director at Age UK, said the report should be "a wake-up call" and that it was worrying how many older people were struggling to reach a hospital or their local GP.
She added: "It is crucial that older people are able to get out and about, especially as the evidence shows this helps them retain their health and independence for longer.
"The bus pass is an absolute lifeline for many who would otherwise be stranded at home and is utterly essential, but the truth is it's not enough on its own to enable older people to stay mobile.
"For example, better transport planning and more imaginative use of volunteers could make a big difference today, and in the medium term driverless cars and other technological innovations could be real game changers."


Police in Scotland have said they remain alert to all terrorist threats after a report that a woman in Glasgow may be poised to carry out an attack.

A Sky News investigation claims that individuals are being recruited by so-called Islamic State as "lone wolf" bombers in the UK.
Using fake identities reporters said they were told about a woman in Glasgow who was "ready to attack".
Police Scotland said it was working with the Metropolitan Police.
Officers have urged communities to report any suspicious activity.
Sky News said journalists created fictional characters online who were able to interact with so-called Islamic State recruiters.
The Sky team reported getting in touch with a married couple who are from the UK but based in Syria.
The undercover reporters said they were sent terror guidebooks by senior jihadists - including advice on raising funds and making weapons.
They said the female jihadist told them that this Saturday's VJ commemorations involving the Queen and the Royal Family were a target.
She is also said to have told them she had a potential female bomber in Glasgow.
Assistant Chief Constable Ruaraidh Nicolson, from Police Scotland's organised crime, counter terrorism and safer communities team, said: "Police Scotland is working with the Metropolitan Police following media reporting about potential terrorist activity in the United Kingdom.
"The threat level in the UK remains at 'severe' which means an attack is highly likely.
"Against that backdrop Police Scotland constantly assesses and reviews its response to the threat from terrorism with policing operations being shaped appropriately and based on the latest intelligence analysis."
He added: "I would like to reassure the public that we are working closely with our security partners and we remain alert to all terrorist threats that may manifest here or where individuals overseas may seek to direct or inspire others to commit attacks in and against the UK.
"I would ask that communities remain alert for any suspicious activity and report it to the police so we can take the appropriate action required.
"Communities are our biggest ally in the threat against terrorism."


A suspected brothel has become the second to be shut down in Reading within a week.

A closure order was approved on Tuesday following a Thames Valley Police operation in Radstock Road.
One man found at the premises was suspected of paying for sexual services, while two women were placed in the care of a support agency for victims of exploitation.
It followed the closure of a suspected brothel in Bedford Road on Friday.
Closure orders granted on both properties prevent anyone from entering them for three months.
Insp Keith Stacey said three brothels have been closed in the area during the past two months.
He added: "We have become more aware of off-street prostitution in the form of brothels in the town and, in this instance, the enterprise was being carried out in an area populated by lots of families and near two schools.
"We have also been made aware that innocent families have had men at their door wrongly thinking that they were at the brothel."
Anthony Brain, head of community safety at Reading Borough Council, said tackling exploitation "in all its forms" was a priority.


European Union officials have accused Mastercard of overcharging consumers with the fees the company charges.

"We currently suspect Mastercard is artificially raising the costs of card payments," said the EU statement.
Those fees harm consumers and retailers in the EU, competition commissioner Margrethe Vestager said.
The credit card company said it was "working with the European Commission on the issue" and was preparing a formal response.
"Throughout this procedure we have kept the needs of both consumers and merchants in mind," Mastercard said.
The EU is focusing on what is known as 'interchange fees' - the fees retailers pay banks to process card payments.
Officials say they are concerned that Mastercard violates competition rules by requiring retailers to pay artificially inflated fees to process credit card transactions.
They say this practice leads to higher prices for retailers in the EU, which they then pass on to consumers.
The charges from the EU are part of a long-running investigation.
The maximum fine that the EU can impose for antitrust infringements is 10% of the company's annual sales, according to the EU.
A separate investigation into Visa's interchange fees is also being carried out by the EU.


A campaign for Cardiff to have Wales' first directly elected mayor will be launched in January.

It will be organised by Daran Hill, a key figure in the successful 1997 and 2011 devolution referendum campaigns.
He told BBC Wales the campaign will have cross-party support and a budget of between £20,000 and £30,000.
To get a Yes/No referendum on Cardiff having a directly elected mayor, 24,647 signatures - 10% of the electorate - must be collected over six months.
The earliest potential date for that referendum would be autumn 2016.
If the Yes side were to win, a Cardiff mayoral election could then be held in the summer of 2017.
There are currently 17 directly elected mayors in England, with more on the way, but there are none in Wales.
Ceredigion is the only Welsh local authority to have had a referendum on the matter.
Voters there rejected the idea in 2004 by a margin of nearly three to one.
The leaders of all 22 local authorities in Wales are elected by their fellow councillors, rather than directly by voters.
Mr Hill said having an elected mayor was a "new, fresh idea" that he believed would "energise the people of Cardiff".
"The vision and the idea is to give the people of Cardiff a say at long last as to whether they'll have an elected mayor to represent the whole of the city," he said.
"To take us forward to a new political level that'll make us fit, I suppose, for the 21st Century."
Mr Hill said the "pressure" for having a mayor was coming from other cities.
"We see Bristol has had an elected mayor for a long time, there's a big push across the north of England," he added.
"I think for a city with size, Cardiff needs that extra momentum."
But Cardiff North Labour AM Julie Morgan is sceptical about the idea.
"It's a difficult, complicated, expensive way of going about getting a mayor, and there are no proven benefits," she said.
"It's also completely the wrong time because we're talking about local government reorganisation, where local authorities are coming together, we're talking about a City Region.
"I'm a great believer in collective responsibility from whatever party may be in power, and I think with an elected mayor you do get the power concentrated in one person."


Plaid Cymru leader Leanne Wood keeps in touch with SNP leader Nicola Sturgeon via instant messaging in the run-up to the general election, she has revealed.

Ms Wood told BBC Breakfast she spoke fairly regularly to the Scottish first minister adding: "We're in touch via messaging as well, online."
The pair had not discussed potential future prime ministers, she said.
"It's not about personalities. It's about politics and policies," Ms Wood told the programme.
If the smaller parties hold the balance of power, SNP, Plaid Cymru and the Greens would work to "present the alternative to austerity regardless as to who are the key people involved".


One man has been convicted over serial blasts in India's capital Delhi that killed 60 people in 2005.

Tariq Ahmed Dar, who police accused of masterminding the attacks, was sentenced to 10 years in prison for funding terrorism.
Two others, who were accused of murder and attempted murder, have been acquitted of all charges.
India had blamed militant group Lashkar-e-Taiba for the attack on three busy marketplaces in the city.
The casualty figures were high because the blasts occurred days before the Hindu festival of Diwali, which is celebrated on a grand scale in Delhi.


A man in his 20s has been taken into custody after a homeless man was found severely burned in Nairn.

Police Scotland said the 34-year-old victim suffered burns on his lower body in the Tower Court area of Nairn at 22:44 on Tuesday.
He was taken to Raigmore Hospital in Inverness before being transferred to a specialist burns unit at St John's Hospital in Livingston.
The injured man has been named locally as James Shaw.
A police spokesman said: "As part of ongoing enquiries into a reported serious assault in Nairn where a 34-year-old man received burns to his lower body, Police Scotland can confirm that a man in his 20s is currently in custody in connection with the incident.
"The injured man remains at St John's Hospital in Livingston where he is reported to be in a stable condition.
"High visibility patrols continue to be carried out in the Nairn area to provide reassurance to members of the public."


The people of Chad are going to the polls to vote in presidential elections with incumbent President Idriss Deby expected to win a fourth term.

The main opposition figures are boycotting after their demands for electoral reform were not met.
There are concerns that the boycott could affect voters turnout.
Mr Deby, who has faced two attempted coups since the last polls, has recently mended relations with Sudan, where rebel fighters were based.
The BBC's former correspondent in Chad, Celeste Hicks, says this has helped to restore security and it is significant that Monday's election is taking place in relative peace.
Chad became an oil-producing nation in 2003, but remains one of Africa's poorest countries.
Mr Deby is facing two challengers: a lawyer, Nadji Madou, and a former agriculture minister, Albert Pahimi Padacke. However, both are relatively unknown.
Many voting stations in the capital, N'Djamena, opened late because of the late arrival of voting materials and staff, the AFP news agency reported, quoting witnesses.
By Celeste HicksBBC News
For many Chadians, Monday's election is a foregone conclusion. With three of the most popular opposition politicians not taking part, it seems unlikely that Idriss Deby will face much of a challenge from the two candidates who are standing. Nadji Madou is a newcomer on the scene, a wealthy lawyer from the south; he may hold some appeal to younger voters, but lacks political experience. Albert Pahimi Padacke has a longer political career, but most of that has been as a minister in Mr Deby's government.
The apathy evident in some voters seems in part to spring from disaffection with February's legislative elections which many feel were badly organised. The rest is frustration with an electoral system that has consistently failed to offer real choice since Chad made the transition to multiparty democracy in the late 1990s.
Although President Deby will feel that he has shown Chadians the benefits of his 20-year tenure, including oil income spent on new hospitals, roads and schools - and perhaps more importantly bringing an end to the disastrous rebellions sponsored by Sudan - Chadians' real feelings will emerge when its known how many of the 4.8 million registered voters actually turn out.
Three of Chad's more prominent opposition figures, Ngarlejy Yorongar, Saleh Kebzabo and Wadal Kamougue, pulled out of the race after a list of demands to improve the electoral process was not met.
Most serious of these was a request to reprint voters cards, after Mr Kebzabo found a number of pre-dated cards on sale in N'Djamena's main market.
Some results from recent legislative elections were also annulled after the country's constitutional court found irregularities.
A coalition of rebel groups has also called on people not to vote, describing Mr Deby as the "Sultan of Chad".
He has been in power for more than 20 years after seizing power in a military coup, and changed the constitution in 2004 to scrap the two-term presidential limit.
Attempts by other African leaders to stay in power for more than two terms have proved unpopular - in neighbouring Niger the president was last year ousted by the army after he tried to extend his rule.
Since Chad's last elections rebels have twice travelled 1,000km (about 600 miles) from the east to the capital to overthrow Mr Deby, angered by his decision to change the constitution.
They were supported by the Sudanese government, which was unhappy with Darfuri rebels taking sanctuary in the east of Chad.
A rapprochement between Chad and Sudan in 2010 has helped bring peace to the region.


Jockey Frankie Dettori has been given a six-month ban from racing after failing a drugs test in France.

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The 41-year-old, who has more than 3,000 career wins, tested positive for a banned substance on 16 September.
The suspension imposed by French racing authority France Galop will run until 19 May 2013, and will apply worldwide for the three-time champion jockey.
In a statement Dettori said he "has let down the sport he loves"  but most of all "his wife and children".
The substance, discovered after a test at Longchamp racecourse, has not been disclosed, although Dettori's solicitor said it was not a performance-enhancing drug.
Dettori will miss the start of the British Flat racing season on 23 March and the Dubai World Cup, the world's richest race, a week later.
He will also sit out the opening Classics at Newmarket's Guineas meeting in May but he will be back in time for the Epsom Derby, which he won with Authorized in 2007, on 1 June.
Solicitor Christopher Stewart-Moore said he had spoken to father-of-five Dettori and he had no arguments with the decision by France Galop.
"He also accepts that he has let down the sport he loves and all those associated with it, as well as the wider public. But most of all - and this is his greatest regret - he has let down his wife and children," he said.
"He is enormously grateful for the opportunities that he has been given by owners and trainers over the years, and for the support of his many fans.
"Racing has been good to Frankie, and he knows that his privileged position brings with it responsibility. For this reason, he is determined to rebuild his reputation when he returns to the saddle in six months' time."
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The British-based Italian rider, who made history by riding all seven winners on one card at Ascot in 1996, has taken responsibility for his failed test.
"Frankie could make excuses - he has, after all, regularly been tested for prohibited substances throughout his career," said his solicitor.
"He is clear, however, that the responsibility for his current situation lies squarely with him. From the start of France Galop's inquiry, he has acknowledged to them that he has made a mistake and that the fault was his."
The jockey, who was given a police caution in 1993 for the possession of a small amount of cocaine in London, is not the first rider to breach the French rules.
Six-time champion jockey Kieren Fallon was banned for six months by France Galop in 2006 and then suspended for a further 18 months after a second positive drugs test in August 2007.
There are more than 400 professional jockeys in Britain. Between 2005 and 2011, a total of more than 6,000 breath and urine tests were carried out, of which seven were failed drugs tests and 13 breached the alcohol guidelines.
"This is nothing short of a catastrophe for the image of British racing.
"Frankie Dettori is so much more than a brilliant, world-class jockey: his bright personality, debonair looks and Italian/cockney accent have made him by far the sport's best-known character.
"Consequently, he's been considered just right to promote racing across the media, but that persona now lies in pieces.
"Back in 1993, when Dettori received a police caution for possessing cocaine, it was put down to youthful indiscretion and quickly forgotten.
"In a quite different era, as the jockey plans for life after Godolphin as a freelance, it remains to be seen just how long it takes to recover from this episode. "
The Professional Jockeys' Association (PJA) insisted the sport did not have a widespread problem with drug use, but chief executive Paul Struthers acknowledged riders did have to contend with keeping their weight down, and the possibility of falls.
"As well as all the normal pressures that other sportsmen and women have to contend with, unlike many other sports jockeys have the added pressures of massively reduced calorific intake and are constantly at very real risk of serious injury," he said.
Dettori, who passed six tests in Britain during 2012, gave the positive test at a Sunday meeting which was a day of major trials for October's Prix de l'Arc de Triomphe meeting.
The jockey had four rides at Longchamp that day.
Dettori rode Marco Botti's Joshua Tree to third in the Qatar Prix Foy, while the John Hammond-trained Sarah Lynx trailed home last in the Prix Vermeille.
He was then beaten by a head into second on the Godolphin-trained Farhh in the Prix du Moulin and was third on stablemate Willing Foe in the Prix Gladiateur.
In October, the jockey announced he was to split with Sheikh Mohammed's Godolphin operation after an 18-year association and go freelance from 2013.
Dettori has won 14 British Classics and is also a three-time winner of France's prestigious Prix de l'Arc de Triomphe, on Lammtarra in 1995, Sakhee in 2001 and Marienbard the following year.