Thames Water has been fined a record £20m after pumping nearly 1.5 billion litres of untreated sewage into the River Thames.

The company admitted water pollution and other offences at sewage facilities in Buckinghamshire and Oxfordshire.
Fish and birds died following the spills in 2013 and 2014.
The £20.3m fine is the largest penalty handed down to a water utility for an environmental disaster.
Judge Francis Sheridan said the scale of the problem was such that it must have been known up the chain of command.
He told Aylesbury Crown Court it was inconceivable that all the individual managers made the same decisions to run pumps at half levels, calling it a "shocking and disgraceful state of affairs".
He added: "It should not be cheaper to offend than to take appropriate precautions."
The spills occurred at four Thames Water Utilities Ltd sewage treatment works, at Aylesbury, Didcot, Henley and Little Marlow, as well as a large sewage pumping system in Littlemore in Oxford.
Hundreds of fish were killed and sewage spilled into nature reserves, while nappies and other debris went into the Thames and the adjoining River Thame.
Manholes also overflowed and fewer dragonflies were reported.
Environmental damage was caused in the riverside towns of Henley and Marlow.
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Company director Richard Aylard said: "We have failed in our responsibility to the environment and that hurts both personally and professionally, because we do care.
"We've also failed in our responsibility to our customers who pay us to provide an essential public service all the time, every day and not just some of the time, and we apologise for all of those failings."
Judge Sheridan said the company had a "history of non-compliance" and that managers had ignored warnings and "risks identified by employees and others".
Staff recorded a "failure waiting to happen", he said.
Robert Davis, from the Environment Agency, called it some of the worst pollution he had witnessed.
He added: "I couldn't believe what I was seeing. The river was visibly polluted bank to bank with sewage.
"It was grey, it was lifeless, it had fish floating along it, and was polluted as far as the eye can see both downstream and upstream. It was really sad to see such a beautiful river so badly polluted."
Farmer Michael Woodford built a 3km [1.9 mile] fence to make sure his cattle did not access the water at the time.
He said: "We were very concerned about the welfare of our cattle.
"This type of pollution is very harmful to livestock and could be fatal to animals.
"It was shocking because the river was a haven of wildlife. There were always fish and crayfish in there. The whole of the wildlife was being destroyed by all this pollution."
Chief executive of Thames Water Steve Robertson said he deeply regretted the spills but claimed things at the company had improved since it had increased staff in key roles.
"We understand our huge responsibilities to the environment, have learned from these serious events and continue to invest at the rate of around £20m a week on continually improving our service to our customers and the environment."
The company has 21 days to pay the fine.
The previous largest fine handed down by a court was £2m, given to Southern Water in December after sewage was discharged into the sea near Margate.
Anne Brosnan, chief prosecutor for the Environment Agency, said: "Thames Water was completely negligent to the environmental dangers created by the parlous state of its works.
"Our investigation revealed that we were dealing with a pattern of unprecedented pollution incidents which could have been avoided if Thames Water had been open and frank with the Environment Agency as required by water company industry protocol."
This is by far the largest fine Thames Water, or any UK water company, has ever been landed with.
However, the record sentence is not a surprise.
Fines for these types of offences have been going up since new guidelines were introduced in England and Wales in 2014.
Also Judge Francis Sheridan said more than once during this case that he wanted to send a message to shareholders that pollution on this scale is not acceptable.
However, the fine amounts to a tiny proportion of the company's annual income. Thames Water makes an operating profit of around £2m every day.
Louise Bowe, River Thame Conservation Trust chief executive, said: "We have been shocked as the catalogue of events from 2013 have come out in court.
"It was much worse than we thought and explains how the devastating damage to the river came about.
"Poor quality sewage effluent being released reduces oxygen in the water. Fish and other aquatic wildlife struggle to survive and the whole ecosystem can be damaged for many years.
"Some large fish that were killed cannot be replaced as species like large mature chub and roach are simply not available."
Doug Kennedy, from Cuddington, set up the Save the River Thame project after being "appalled" by the spills.
He said: "I was very shocked to find large dead fish on the river. The river was black. It had rather horrid little black flies bouncing over it. You couldn't see into it, it was just horrible.
"It's absolutely disgusting what was going on [at the sewage treatment works]… but we weren't aware of it.
"[There was] floating disgusting material - raw sewage - on the River Thames, as well as on the Thame."
Rose O'Neil, water policy manager at the WWF, said it was "not an isolated issue".
She added: "There are around 15,000 sewer overflows across England releasing raw sewage into our rivers.
"This case highlights the need for water companies to invest in solutions that manage the whole local catchment area such as green infrastructure and sustainable drainage systems. They simply can't continue treating our rivers as their dumping ground."


Three men are "lucky to be alive" after they were thrown from their fishing boat off Anglesey.

Moelfre RNLI lifeboat station raised the alarm at 13:20 BST on Friday after a crew saw the incident unfold in Moelfre Bay.
The three men struggled to swim to safety while their boat continued under its own power.
"We saw their boat circling close to them and imagined the worst," said Moelfre lifeboat helm Vince Jones.
"Fortunately, by the time we had launched, the strong winds had blown it clear of them," he added.
Two of the men were rescued by a local fishing boat, while the third man, aged 60, was found exhausted and clinging to a buoy without a lifejacket.
They were all taken on board the inshore lifeboat and brought back to the lifeboat station
Mr Jones said: "The three men thrown in the water are lucky to be alive and completely uninjured.
"The boat's engine had an emergency kill cord but it had somehow come detached from the person driving the boat when it capsized. Someone was watching over these guys today."


Commons sources say the government is to propose a compromise deal on the funding opposition parties are entitled to - and put it to a vote next week.

There has been a row brewing at Westminster for some time over cuts to so-called Short money.
But sources are confident MPs will back a plan that will save 10% from the total in a vote expected on Wednesday.
Ministers say Short money payments are unduly generous given cutbacks elsewhere in the public sector.
In November, George Osborne's Autumn Statement revealed plans to cut the funding - named after former Labour MP Ted Short - by 19%, saying this would be in line with savings expected of unprotected Whitehall departments.
The plans have been strongly criticised by opposition parties.
The proposed compromise would shift the formula for calculating the payments from taking account of the Retail Price Index to instead using the Consumer Price Index.
Over the last 12 months the CPI has grown by a far smaller rate than the RPI - so the switch makes the new formula less generous.
It will necessitate what a source described as "much greater transparency" over what the money is spent on.
In addition, it will set a floor below which Short money cannot fall for the smallest parties in the House of Commons - those with between one and five MPs.
That floor is Â£75,000 a year. There is also a ceiling for those parties, of just over Â£200,000.
Between now the end of the decade sources claim the compromise arrangement will save the taxpayer around Â£3.5m.


League One's bottom club Shrewsbury Town have confirmed the appointment of Grimsby Town boss Paul Hurst as their new manager.

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Shrewsbury had been in talks with Hurst for several days after making an approach for the 42-year-old, who left his post with the Mariners on Monday.
Hurst joined Grimsby in March 2011 and won promotion back to the English Football League last season.
He replaces Micky Mellon at Shrewsbury, who have not won in nine league games.
Hurst will be joined at Greenhous Meadow by his assistant at Grimsby Chris Doig.
Shrewsbury, who have won only twice in the league this season, have been managerless since Mellon left on 7 October to take over at National League side Tranmere.
The club are bottom of the table, six points adrift of 20th place ahead of Hurst's first match in charge on Saturday at Southend.
BBC Radio Shropshire's sports editor James Bond:
Hurst fits the bill Shrewsbury were demanding - a young manager with drive and ambition.
After promotion with Grimsby last season, he has already taken them into League Two's top six.
He will provide a much-needed morale boost at Shrewsbury, who have slumped to four defeats in a row since Mellon's exit.
It will also perk up Town fans, who were not slow in expressing their frustrations after Saturday's 4-2 home defeat by Northampton.


Phillip Chiyangwa, vice president of the Confederation of African Football's (Caf) Africa Cup of Nations committee, says Zambia may yet be given an opportunity to bid to host the 2021 Nations Cup.

Chiyangwa said Caf was reviewing the manner in which the 2019, 2021 and 2023 Africa Cup of Nations tournaments were awarded to West Africa by the previous Caf administration.
Chiyangwa, who is also head of the Cosafa region (Council of Southern African FA's) spoke of his concerns in April and wants the tournaments to be more widespread.
You as Zambia, if you are ready, you may have an opportunity that arises in 2021
"I am the giver and taker of competitions," Phillip Chiyangwa said during a tour of Zambia last week.
As things currently stand, the 2019 edition will be held in Cameroon while Ivory Coast is set to stage the 2021 tournament and Guinea will be hosts in 2023.
That means the west of the continent would have staged Africa's showpiece event for five consecutive tournaments, from 2015 - when Equatorial Guinea stepped in for Morocco - to 2023.
"I am currently reviewing what happened in the past, there may be possibilities in 2021 going forward, but the reason why I want to be ready with my region is to know which country wants what.
"If an opportunity arises there is no need for me to do last minute searches," Chiyangwa said.
"Our review process is that we go to those countries that bid for those competitions."
Chiyangwa said that the change at Caf was driven by a sense of unfairness in the manner tournaments were awarded to hosts under its former president Issa Hayatou.
"Our contestation on Hayatou to continue in office was the unfair awarding of tournaments to one region," he said.
"Other regions were suffering, if you look at the background of the Issa Hayatou fall, it arises out of the fact that most of the competitions were being awarded to West Africa, not North Africa, not even Central Africa and not even Southern Africa," he added.
"So the chance you have - should in our investigations a decision be arrived at to nullify the other competitions - you as Zambia, if you are ready, you may have an opportunity that arises in 2021."


A judicial tribunal which investigated whether Police Scotland breached spying guidelines has ruled the force acted "unlawfully."

It looked at the cases of individuals whose data was accessed as the force tried to determine how information about a murder probe reached the press.
The tribunal ordered a journalist whose communications were intercepted should be paid Â£10,000 in compensation.
An independent inquiry into Police Scotland's actions has been announced.
The Interception of Communications Commissioner ruled in November 2015 that officers had broken new spying regulations by obtaining communications data without permission on five occasions.
Officers had been attempting to find out how information about the investigation into the murder of Emma Caldwell in 2005 had appeared in the media.
Sir Stanley Burton said the "failures" by police "could properly be seen as reckless".
This latest ruling from the Investigatory Powers Tribunal (IPT) came after a hearing took place in Edinburgh last month.
Two former police officers, and their wives, together with two serving policemen, took the action against the force to "complain of the collateral interference with their privacy".
Gerard Gallacher, a former police officer who carried out an 18-month journalistic investigation into the case, is to be paid Â£10,000 after telling the tribunal he had suffered an "invasion of privacy, familial strife, personal stress and strain and loss of long-standing friendships" as a result of Police Scotland's actions.
The IPT ruled the interference with his rights to freedom of expression were "serious in respect of the obtaining of more than 32 days of communications data".
Of the six complainants, only Mr Gallacher and his wife had been seeking compensation.
The tribunal also ordered that an inquiry into the breach of guidelines by police be conducted by a senior officer "from another police force in the United Kingdom other than Scotland, and without any previous relevant connection with Police Scotland".
At the end of July, Phil Gormley, the Chief Constable of Police Scotland, asked Mike Barton, Chief Constable of Durham Constabulary, to head an independent investigation into the issue.
Responding the the IPT judgement,  Police Scotland Deputy Chief Constable Iain Livingstone said the force would "consider and act" on the findings.
He added: "Police Scotland has fully accepted that standards fell below those required in this case. It would be inappropriate to comment further at this stage given the investigation to be conducted by Chief Constable Barton.
"Following the breach, a full review was immediately conducted to ensure there could be no repeat of the circumstances which led to the IOCCO determination, which Police Scotland accepted."
Det Insp David Moran, one of the complainants in the case, welcomed the judgement from the IPT.
He said: "That there is to be an inquiry by an external police force into the circumstances surrounding the affair is a large step forward, however I have concerns that Police Scotland have invited the Chief Constable of Durham Constabulary to examine the outstanding 'non-criminal' matters only.
"I do not believe that is in the spirit of what was discussed at the IPT hearing on July 22 and that all matters, whether potentially criminal or non-criminal, should be on the agenda for a new independent and impartial enquiry."
Last year, Mr Moran contacted MSPs on Holyrood's Justice Committee, saying he had been falsely identified as the source for a newspaper article about the Emma Caldwell murder investigation and this has left his reputation "severely scarred".
He said the tribunal judgement stated Police Scotland had "no intelligence" suggesting he was involved in leaking information.
David Kennedy, deputy general secretary of the Scottish Police Federation, said: "This judgement leaves no doubt that the actions of the Police Service of Scotland towards our members (and others) breached their human rights.
"The SPF had no hesitation in supporting our members seek remedy for this breach and we sincerely hope the service will reflect on this ruling when considering their future actions."


Sri Lanka's president has promised to seek reconciliation on the sixth anniversary of the army's victory over Tamil Tiger separatists.

Maithripala Sirisena said the truth of what happened in the conflict needed to be established and justice delivered.
On Monday for the first time Tamil politicians in the former war zone in the north and east were allowed to hold a memorial event for dead civilians.
However, police surveillance was high. Other demonstrations were banned.
"We were all happy when the war ended. But can we be happy with the developments post-war?" Mr Sirisena said during commemorations on Tuesday.
"We were not able to win hearts and minds of people. The true reconciliation could only be achieved by winning hearts and minds."
In a statement issued on Sunday, Human Rights Watch expressed doubts about the new administration's commitment to address the allegations of human rights abuses and war crimes during the last stages of the civil war.
Mr Sirisena's remarks, however, are another sign of a changed emphasis since his unexpected election victory over the more nationalistic former president, Mahinda Rajapaksa, in January, reports the BBC's Charles Haviland.
Our correspondent says Mr Sirisena appears to be acknowledging that more remains to be discovered about how many Tamil civilians died or disappeared in murky circumstances - and about whether Tamil Tiger leaders were killed after surrendering.
There are also many more unsolved rights issues dating back decades.
For the past five years, the war's end was celebrated as "Victory Day" by the Rajapaksa government, but the new administration has said it will be observed as "Remembrance Day" to mark the sacrifices made by all those died, irrespective of their ethnicity, reports BBC Sinhala's Azzam Ameen.
Monday's memorial event by Tamil politicians was another notable change.
The ceremony was conducted on the beach of Mullivaayikkal in Mulaithivu district where the final battle took place. The ceremony was attended by the Chief Minister of the Northern Province CV Vignaswaran and many other members of the provincial council.
Since 30 years of civil war ended in May 2009, annual victory day military parades in Sri Lanka have been held with tanks and artillery, while fighter jets fly overhead.
In contrast, the Tamil community in the north and east was prevented from any attempts at public memorials. Political party offices and media institutions were surrounded by government troops and roads to some Hindu religious shrines closed in order to deny any attempts at commemoration.
But this year, things were different.
Monday's ceremony at Mullivaayikkal was part of Remembrance Week, which began on 12 May. Several religious events were held throughout the north and east to commemorate the civilian lives lost.
According to UN estimates, between 80,000 and 100,000 people were killed in the conflict. Some reports have suggested about 40,000 Tamil civilians may have been killed in the final few weeks.
Peace campaigners have repeatedly warned against major victory celebrations that could further alienate the country's communities.
Mr Rajapaksa and his supporters commemorated the war anniversary separately on Monday and blamed the new government for not celebrating it as a victory.


"This is, I think, one of the most historic attacks on climate and environmental action that the US has ever seen," said Liz Perera from the Sierra Club.

Her words are certain to cheer Trump supporters everywhere.
Green "job-killing" regulations limiting energy production have long been a red rag for Donald Trump, as candidate and President.
His new energy independence executive order seeks to radically change the US narrative on climate change, its causes and its importance.  The best way of fighting global warming according to the new outline is to create prosperity. Environmental regulation should be about air and water. CO2, in this light, is your friend.
Supporters believe that cutting back Obama climate regulations will create thousands of jobs in the newly liberated oil and gas industries.
His opponents agree the new order will be a job creator - but they'll be jobs for lawyers, not in the coal fields.
Front and centre is practical action on the Clean Power Plan (CPP), the Obama project to cut fossil fuels from electricity production. Although it has long been tied up in the courts, the CPP will be left to fester there while the new administration comes up with a much weaker replacement.
"Undoing the rule will not be straightforward," said Prof Bruce Huber, from the Notre Dame law school.
"For the Environmental Protection Agency (EPA) to reverse course, it will have to propose a new rule, with all the lengthy procedures that entails. When President George W Bush tried to reverse course on some of President Clinton's signature environmental regulations, those efforts took years and were not entirely successful."
In terms of coal, the new executive order will allow the Department of the Interior to lift a moratorium on the sale of new coal leases on federal lands. However, boosting coal as a source of energy, and jobs, will be very difficult.
Many coal plants have shut down not because of Obama's carbon restrictions but because of mercury pollution associated with burning the fuel. Thanks to fracking, cheap natural gas has soared as a source of power generation, and renewables are taking an every bigger share.
Former State department climate adviser Andrew Light now works for the World Resources Institute. Both of his grandfathers were coal miners.
"They were paid by the tonne for the coal they pulled out of the ground, but those jobs are gone, and technology has moved beyond that and I hope it's the case that voters in the coal states will recognise that their jobs aren't magically coming back because of this executive order," he told BBC News.
President Obama sought to put consideration of climate change at the heart of all government policy - but by revising the social cost of carbon measure and encouraging an immediate government review of all rules that inhibit energy production, President Trump is signalling a change in the widely held philosophy that CO2 is the enemy, the main driver of climate change.
While rolling back Obama era ideas like the role of climate change in national security, or how climate change should be considered in relation to the National Environmental Policy Act, the Trump plan does not directly attack the key finding on which much of America's carbon restrictions are based.
Back in 2007, the US Supreme Court ruled that carbon dioxide gas was a pollutant under the Clean Air Act.
In response, the EPA ruled in 2009 that CO2 and other gases were responsible for contributing to climate change which results in a threat to the public health and welfare of current and future generations.
This "endangerment finding" compels the federal government to regulate emissions of CO2. And according to some environmentalists, this finding is the solid rock that Trump's plans will be dashed against.
"The law of the land is that CO2 endangers my public health and welfare," said Liz Perera from the Sierra Club.
"So they have to regulate it. What they are doing now is saying that all the Obama regulations were wrong but that means they are going to have to put something forward in their place and by the law it has to be adequate or we can sue them every step of the way."
Other experts believe that the ultimate goal of this executive order will be to overturn the Supreme Court ruling on CO2 as a pollutant.
They believe that the declaration of EPA administrator Scott Pruitt that CO2 was not a "primary contributor" to climate change is instructive of the direction of travel.
"It is fundamental," said Andrew Light. "I believe that Scott Pruitt wants to go after the endangerment finding. Their argument is that climate change exists, but it is not the case that humans are causing it.
"It is the endangerment finding that draws that tight connection between the fact that humans are making it and the fact that global warming is happening. Once you destabilise that point then you can go for the endangerment finding.  That would be the biggest win they could get."
But Liz Perera, for one, believes that won't happen.
"We have the economics on our side, we have the market on our side,  we have the public on our side, and we have the law on our side - that this is endangering public health and welfare. They can't change any of those things."
But in many ways, extended court battles are exactly what President Trump and the fossil fuel lobby are looking for.
"Delay is what they want," one green source told me. "Delay is winning."
Follow Matt on Twitter and on Facebook.


Theresa May has "full confidence" in Philip Hammond, Downing Street has said, after reports the chancellor was trying to slow progress towards Brexit.

Some newspapers say colleagues believe Mr Hammond is attempting to "undermine" the process by delaying decisions on migrant curbs.
But a Treasury source told the BBC the claims were "rubbish".
The prime minister's spokeswoman said the chancellor's focus was "on how best to approach" Brexit negotiations.
This comes after the Daily Telegraph reported that Mr Hammond was one of a number of voices urging caution about plans for a new work permit system designed to reduce immigration that was discussed at a Brexit cabinet committee meeting.
It said Home Secretary Amber Rudd had presented plans for a post-Brexit visa regime that would see all EU workers forced to prove they had secured a skilled job before being allowed into the UK.
The newspaper said the plan was seen as confirmation that the UK would leave the single market as part of the Brexit process, something it said Mr Hammond was previously understood to have warned against.
The paper quoted a source as saying: "He is arguing from a very Treasury point of view. He is arguing like an accountant seeing the risk of everything rather than the opportunity."
The Telegraph said there were claims on Sunday that tensions had increased to the point of creating fears Mr Hammond could resign as chancellor.
The Times, meanwhile, reported that Brexit-supporting ministers believed Mr Hammond was "not following Theresa May's instruction that government 'get on' with Brexit".
Conservative MP Jacob Rees-Mogg, who supported the Leave campaign, accused Treasury officials of "negativity" towards Brexit.
He told BBC Radio 4's The Westminster Hour they were "reheating" the referendum campaign briefings from the Remain-supporting ex-Chancellor George Osborne.
One Whitehall source told the BBC that it was natural that the current chancellor would want to think through the implications of any proposals for the City of London.
However, there was a growing consensus that what was described as "high-value immigration", seen to benefit the City, should not be affected by Brexit, the source added.
But Health Secretary Jeremy Hunt said the cabinet was "absolutely united" in wanting to get its decision right.
He told BBC Radio 4's Today programme: "We must go through all the options. This isn't the first time in the history of government where you read reports in the newspapers that may not actually reflect what's happening."
Liberal Democrat Treasury spokeswoman Baroness Kramer said: "You don't have to be an accountant to realise the huge risks of 'hard Brexit' to jobs, wages and our economy.  Just because some members of the cabinet wish to hurl us off the economic cliff, doesn't mean everyone else is under some obligation to act like lemmings."


A 62-year-old man has been charged over damage caused to more than 50 cars on Teesside.

The man from Stockton, is charged with criminal damage, possession of a bladed article and driving without insurance.
Cleveland Police said it followed "an incident in which 56 vehicles were damaged in Errol Street and surrounding roads in Middlesbrough" on 20 October.
A force spokeswoman said the man is due before Teesside magistrates on 8 February.


Wigan Warriors ran in seven tries without reply as they pulled off a comprehensive victory against an under-strength Leeds Rhinos side.

Michael McIlorum scored his first try of the season to put Wigan ahead and Sam Tomkins touched down soon after.
George Williams, who kicked just two conversions from six attempts, scored Wigan's third try before the break.
Oliver Gildart scored twice in quick succession before Tom Davies and Williams wrapped up a comfortable win.
Leeds, who could not finish lower than second before the Super 8s split going into the game, rarely threatened to put points on the board at the DW Stadium.
The hosts dominated the game and their attacking display saw them reach a century of Super League tries scored this term when Davies crossed late on.
Wigan move up to seventh following the win as they moved above Huddersfield after they were defeated by Hull FC.
Leeds, who were without 13 players and gave debuts to Harry Newman, Harvey Whiteley and Alex Sutcliffe, saw their four-point gap on third place cut to three points thanks to Hull's victory.
Wigan coach Shaun Wane:
"It was definitely a no-win situation. We know Leeds were busted.
"We're not patting each other on the back but I liked the manner in which we went about our business in those conditions, which were very testing.
"A 77% completion rate was good, some of our defence was very good and we scored some good tries. We've got 100 tries this season so we're doing something okay."
Leeds coach Brian McDermott:
"I can't tell you I'm happy but I'm not down either. On paper it was going to be a tough night and we had hoped the game would have been closer.
"We are disappointed by the final scoreline and disappointed we didn't score a try.
"But for large parts of the game we put up a fair amount of resistance against a very determined Wigan who were out to respond to their defeat last week.
"There were some good bits in there for us to feel proud of. Once our juniors and also to some extent our senior guys started to fatigue, we conceded some soft tries."
Wigan: Tomkins, Davies, Gelling, Gildart, Burgess, Williams, Leuluai, Nuuausala, McIlorum, Sutton, Isa, Bateman, O'Loughlin.
Replacements: Clubb, Powell, Tautai, Wells.
Leeds: Walker, Briscoe, Keinhorst, Sutcliffe, Newman, Goldin, Lilley, Garbutt, Jones-Buchanan, Baldwinson, Ormondroyd, Ablett, Mullally.
Replacements: Oledzki, Jordan-Roberts, Smith, Whiteley.
Referee: Ben Thaler (RFL).


Two police officers from Scotland Yard's Diplomatic Protection unit have been sacked for sending obscene images from their mobile phones.

The pair, aged 34 and 36, lost their jobs after admitting gross misconduct and being found guilty of a breach of integrity by police chiefs.
The constables were dismissed without notice after the misconduct hearing on Thursday.
They were not named by the Metropolitan Police.
Downing Street police officer PC James Addison, 37, was dismissed in June after sharing extreme pornography on his phone while on duty.
He sent other officers "disgusting and offensive" images that included bizarre sex acts and scenes showing defecation.
The images were found on his phone during the investigation into the so called "Plebgate" affair, in which former government chief whip Andrew Mitchell MP was accused of calling officers plebs during an argument at the gates of Downing Street - an allegation he has denied.
No further action was taken against PC Addison over that matter.
PC Addison, from Rayleigh in Essex, admitted sharing the images and was suspended from duty in December 2013.
In May, at Westminster Magistrates' Court, he was sentenced to a Â£6,000 fine, Â£120 victim surcharge and forfeiture of his mobile phone after he admitted 11 counts of publishing an obscene article.
A total of 14 officers were investigated for either criminal offences or misconduct after the porn was found.
No more criminal action will be taken and the matter has been concluded, the Met said.
Det Ch Supt Alaric Bonthron said: ''The sharing of these images is completely unacceptable."


The case against 13 footballers investigated over alleged spot-fixing has been dropped due to "insufficient evidence", the CPS has said.

Prosecutors said they had looked at the "reliability of the evidence" in light of the collapse of the trial of former X Factor judge Tulisa Contostavlos.
That led to a number of cases linked to journalist Mazher Mahmood, known as the "Fake Sheikh", being reviewed.
The CPS said no further action would be taken against the players.
In April last year, seven players from Football League clubs based in the north-west of England were arrested in connection with alleged spot-fixing, and another six were re-arrested over the claims.
The CPS said it did not believe there was enough evidence to "provide a realistic prospect of conviction".
A statement said: "The reliability of the evidence of one alleged witness in particular had to be very carefully considered in light of recent events in the trial of R-v-Contostavlos and Coombs.
"This was not the only evidence that was considered and when all the evidence submitted by investigators was carefully reviewed in accordance with the Code for Crown Prosecutors, it was decided that there was insufficient evidence to provide a realistic prospect of conviction."
Spot-fixing is where a player corruptly influences a specific element of a match, for example by intentionally getting a yellow card or conceding a corner, without trying to fix the final score.
The original six suspects were arrested after information was passed to the authorities by the tabloid newspaper the Sun on Sunday, for which Mr Mahmood worked.
It was revealed that then-Blackburn Rovers striker DJ Campbell and former Oldham Athletic winger Cristian Montano had been arrested as part of the probe, but both players always denied any wrongdoing.
The newspaper also published claims that former Portsmouth player Sam Sodje had told an undercover reporter that he could arrange yellow and red cards in exchange for money.
At the time, Portsmouth FC said Mr Sodje no longer played for the club but it would co-operate fully with any investigation if it was approached by the authorities.
Ms Contostavlos, who is also a pop star, was accused of brokering a cocaine deal in a newspaper sting led by Mr Mahmood.
During her trial, Judge Alistair McCreath said there were "strong grounds" to believe Mr Mahmood had lied in the witness box.
Ms Contostavlos's rapper friend Michael Coombs was also cleared after he had pleaded guilty to supplying cocaine.
Mr Mahmood, a former reporter for the News of the World, was then suspended by the Sun on Sunday.
Last month, the CPS said it was re-examining criminal convictions in 25 cases where evidence had been given by Mr Mahmood and it had offered no evidence in three live cases where the undercover reporter was a prosecution witness.


Holders Queensland began their 2016 State of Origin defence with a two-point victory against New South Wales in the Sydney opener.

Johnathan Thurston's penalty was overhauled by Boyd Cordner's score but Dane Gagai finished on the right to give the Maroons a half-time lead.
The second half was an arm-wrestle, typified by forward graft and grunt.
Blues' Josh Morris crossed, only for the try to be ruled out as neither side scored points after half-time.
Victory was particularly sweet for captain Cameron Smith, who appeared in his 37th Origin game to pass former team-mate Darren Lockyer as record appearance maker.
Queensland can seal the 2016 series at Suncorp in Brisbane on 22 June, with the return to ANZ Stadium on 13 July.
History is on their side, as 25 of the past 34 series have been won by the winner of the opening game.
Although not quite as tight as 1995's 2-0 Queensland win, the scoreline reflected the desperation of both sides not to concede in this Origin opener, and neither truly sparkled despite periods of pressure.
Queensland and Thurston took a penalty shot early on to put them ahead after failing to breach the Blues, whose indiscipline gave them early defensive work to do.
However the Blues' smart kicking built up pressure in attack that told when James Maloney's short-ball put Cordner through to score the opening try.
Smart hands by the Maroons out wide worked Gagai in for his second in as many appearances before half-time and only brilliant cover defence stopped the Newcastle winger from adding a third after the break.
Desperate scrambling defence at both ends, notably to snuff out teasing kicks, maintained the two-point gap.
New South Wales: Moylan; Ferguson, Jennings, Morris, Mansour; Maloney, Reynolds; Woods, Farah, Gallen, Cordner, Jackson, Bird.
Replacements: Walker, Tamou, Klemmer, Fifita.
Queensland: Boyd; Oates, Inglis, O'Neill, Gagai; Thurston, Cronk; Scott, Smith, Myles, Gillett, Thaiday, Parker.
Replacements: Morgan, McGuire, Guerra, Papalii.
Referee: Ashley Klein (Australia)
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Ian Hutchinson set the fastest speed in Monday's opening Superbike practice session for the Isle of Man TT.

The 11-times winner posted a lap at 129.964mph on his Tyco BMW, marginally faster than Michael Dunlop's quickest speed of 129.497 on a Buildbase BMW.
John McGuinness was third on the leaderboard with 128.871mph.
Yorkshire's Dean Harrison was best of the Superstocks on 128.044mph on his Kawasaki and also topped the Supersport session at 124.461.
McGuinness's Honda team-mate Conor Cummins, New Zealander Bruce Anstey and Michael Rutter made up the top six in the Superbike practice after all registering average lap speeds in excess of 127mph.
Michael Dunlop (126.726) and Lincolnshire's Peter Hickman (125.725), both riding BMWs, completed the top three in the Superstocks.
Harrison's Supersport speed bettered his benchmark from the first practice session held on Saturday night.
Ian Hutchinson (124.156) and Michael Dunlop (124.053) lie second and third in the overall standings for that class.
Ivan Lintin is best of the Lightweight class for Supertwins so far thanks to a lap of 116.773 set on Saturday evening.
John Holden and Andrew Winkle were the fastest sidecar crew on Monday night on 112.055mph.
Practice is scheduled to continue on the Mountain Course on Tuesday evening.


Emergency crews have been dealing with several incidents across Wales after heavy rain and high winds have affected many areas.

In Swansea, a tree collapsed onto a car in Mount Pleasant while residents in Treorchy, Rhondda Cynon Taff, reported flash flooding on the roads.
Gusts of up to 78mph were recorded in Capel Curig, Conwy, around 20:00 BST on Monday.
The Met Office said it would become drier and brighter on Tuesday.
A yellow "be aware" warning of heavy rain for parts of south Wales was in place on Monday evening.
Areas likely to be affected by heavy rain included Caerphilly, Rhondda Cynon Taff, Bridgend, Cardiff, Vale of Glamorgan, Neath Port Talbot, Merthyr Tydfil and Blaenau Gwent.
The gales were likely to affect these areas and also Carmarthenshire, Ceredigion, Conwy, Denbighshire, Flintshire, Gwynedd, Isle of Anglesey, Monmouthshire, Newport, Pembrokeshire, Powys, Swansea, Torfaen and Wrexham.


Almost two-thirds of Italy's farmland has been hit by a prolonged drought, costing Italian agriculture some €2bn ($2.3bn; £1.8bn), farmers say.

Dairy farmers and those growing olives, tomatoes and wine grapes are among the most affected, farmers association Coldiretti warns.
Rome faces eight hours a day without running water after a halt was ordered on pumping water from a nearby lake.
A state of emergency was earlier declared in two northern provinces.
In southern Italy, hundreds of people were evacuated earlier this month, as firefighters battled wildfires.
Coldiretti warns that 60% of farmland is threatened by the drought caused by low levels of rainfall and made worse by a heatwave.
Wine grapes and olive production are suffering throughout much of Italy, amid concerns that a poor harvest could push prices up.
Reports say that milk production has fallen in several areas as cows suffer in the heat.
At least 10 Italian regions are preparing requests to the agriculture ministry for a state of natural calamity to be declared because of the drought, Italy's Ansa news agency quotes sources as saying.
In Rome, utility company Acea has warned of drastic water rationing after the local authorities in the Lazio region ordered the halt to pumping water out of Lake Bracciano, about 30km (19 miles) north of the capital.
The governor of Lazio told Tgcom24 TV station over the weekend that "the truth is Lake Bracciano has fallen too much and we risk an environmental disaster".
He added that only 8% of Rome's water was coming from the lake, urging the city authorities to find a solution quickly.
Earlier this month, Acea began shutting some of Rome's famed drinking fountains.


A former Scottish Conservative candidate who has threatened legal action against the party has accused them of trying to overturn an election.

Belinda Don was originally placed second on the party's list for the European Parliament elections in 2014.
However, the party wants to pass over her in the selection process to replace Ian Duncan, who is standing down as an MEP to work for the Scotland Office.
The Tories said Mrs Don was no longer on their "approved candidates" list.
The party is understood to want Iain McGill, the fifth candidate on their list, to replace Mr Duncan as their MEP.
Mrs Don served as an advisor and parliamentary assistant to former Tory MEP Struan Stevenson for 12 years.
It was reported at the time that Mr Stevenson wanted Mrs Don to be first on the list to replace him when he retired ahead of the 2014 election. The top spot eventually went to Mr Duncan, but he is now leaving Brussels as he is to be given a place in the House of Lords so he can become a Scotland Office minister.
She has not yet filed legal papers at the Court of Session, as Mr Duncan is still currently in place as an MEP. However, she said there were "unequivocal legal arguments" on her side.
Speaking out about the row for the first time, she said she was "deeply saddened that the leadership of the Conservative Party in Scotland seems to think that it is somehow acceptable to overturn the results of an election".
She said: "This is not just an internal party issue, but one that goes to the very heart of our democracy - they are trying to overturn an election result.  In the 2014 European elections my name was on the ballot paper as number two on the list and  231,000 Scottish Conservatives voted for that list in that order.
"Having not received any reassurances that the list order will be respected in these new circumstances, I have prepared a draft writ to demonstrate the unequivocal legal arguments that apply.
"Ms Davidson is now in receipt of this draft writ, and I trust she will now see that the law is clear: the Conservative party does not have any right to remove people from the MEP list on a whim."
The Conservatives contend that to be elected for the party, a candidate must be not only on the relevant list held by the election returning officer, but on the party's own approved list of candidates - a list Ms Don is understood to have been removed from.
A spokesman said: "To become the European Parliament candidate for a region you must be on the approved Scottish Conservative candidates list."
However, Mrs Don contended that she had "remained totally loyal" to the party since the list selection in 2013.
She said: "I have no wish to prolong this regrettable public dispute and remain hopeful that once she is in receipt of clear legal advice, Ms Davidson will see her present course of action is contrary to the law.
"I also press her to take note of natural justice and democracy: no political party should ever seek to ignore the will of their members or the electorate as expressed at both their internal and external elections."


An exhibit by actor Shia LaBeouf that lambasted President Donald Trump has been shut down because it had turned into "a flashpoint for violence".

The piece of performance art encouraged the public to say "He will not divide us" into a camera mounted outside the Museum of the Moving Image in New York.
The Transformers star was arrested after a fracas at the site, which police began manning round the clock.
The actor criticised the museum's decision to shut down the exhibit.
On Twitter, he posted an image of the live stream, which now reads: "The museum has abandoned us."
LaBeouf co-founded the project, which was launched on the day President Trump was inaugurated, on 20 January, with artists Luke Turner and Nastja Ronkko.
The live-stream ran for 24 hours a day, seven days a week, and the artists had planned to maintain it throughout Mr Trump's presidency.
But in the early hours of 26 January, LaBeouf was charged with assault and harassment after a confrontation with a man that was broadcast on the live-stream.
The New York Daily News reported that a number of white supremacists turned up at the site over the past three weeks, including one apparently wearing a Nazi hat.
In a statement, the museum said the atmosphere at the exhibit, named HEWILLNOTDIVIDE.US, "deteriorated markedly" after LaBeouf's arrest.
There had been "dozens of threats of violence and numerous arrests" and it had become "a flashpoint for violence", it added.
"Until public safety concerns overrode the intent of the installation, HEWILLNOTDIVIDE.US generated an important conversation allowing interaction among people from many backgrounds and with different viewpoints," the museum said.
A statement on the exhibit's website says: "On February 10, 2017, the Museum of the Moving Image abandoned the project. The artists, however, have not."


The justice minister has said that a petition by anti-abortion groups claiming 300,000 signatures actually consisted of several petitions collected over 12 years.

Claire Sugden said she received the petition via DUP MLA Jim Wells.
He said it was "the largest petition ever received by the assembly" and signed by Northern Ireland residents.
Ms Sugden revealed that the petition contained signatures from nine campaigns from 2001/2 to 2014.
Addresses from outside Northern Ireland
The minister made the comments in reply to a written question from Paula Bradshaw of Alliance.
She wrote: "There was no petition relating to termination of pregnancy for fatal foetal abnormality and no petition dated after September 2014. There were also addresses identified in the material provided which were not in Northern Ireland."
Mr Wells presented the Precious Life petition to the assembly a week after the Green Party's Claire Bailey presented one containing 45,000 signatures calling for a change to Northern Ireland's abortion laws.
Last month, Stormont sources told the BBC that a working group on fatal foetal abnormality had recommended legislative changes.
Alliance MLA and former justice minister, David Ford recently introduced his private member's bill on abortion to the assembly.
The bill seeks to legalise abortion in cases of fatal foetal abnormalities.
The next stage will take place in the new year.
Unlike other parts of the UK, the 1967 Abortion Act does not extend to Northern Ireland.
Currently, a termination is only permitted in Northern Ireland if a woman's life is at risk or if there is a risk of permanent and serious damage to her mental or physical health.
In February, MLAs voted against legalising abortion in cases of fatal foetal abnormality.
Politicians have been lobbied to reform the law since 2013, when Northern Ireland woman Sarah Ewart spoke out about having to travel to Great Britain for an abortion after she was told she was carrying a baby that had no chance of survival


England caretaker-coach Paul Farbrace says he would find it "hard to say no" if he was offered the job on a permanent basis.

Farbrace, 47, will take charge of the team for the two-Test series against New Zealand, which starts on Thursday.
"I'll give this opportunity a really good go, and if at the end something happens, then great," said Farbrace.
Yorkshire coach Jason Gillespie is among the other contenders to succeed Peter Moores, who was sacked.
The former Australia fast bowler, mentioned as a candidate by new England cricket director Andrew Strauss, told BBC Sport on Tuesday he would "take persuading" to leave Yorkshire.
But the 40-year-old admitted being linked with the England job was "very humbling, very flattering".
England will be without batsman Kevin Pietersen, who has been told he will not be available for selection, despite scoring 355 not out for Surrey against Leicestershire in a County Championship match last week.
After Farbrace said he would be interested in the role full-time, Pietersen wrote on BreatheSport: "He might be the only one who will want a team that's not allowed to be at full strength."
Farbrace, who coached Sri Lanka between December 2013 and April 2014 before becoming Moores's assistant, said England need to improve after drawing their last Test series against West Indies.
Speaking to BBC Radio 5 live's Tuffers and Vaughan Show, he said: "We know we need to play better and finish games off. The Caribbean series was a prime case in point.
"At no stage have we hidden away or made excuses. We have a good group of players and we feel there are exciting times ahead."
Farbrace, who kept wicket for Kent and Middlesex during an eight-year first-class career, admitted to sympathy for Moores but endorsed the credentials of Gillespie, with whom he worked at Yorkshire as second XI coach before taking the Sri Lanka job.
"We were all very disappointed to see Peter move on, he was very popular," he said.
"Jason Gillespie is a brilliant guy, he's done a great job at Yorkshire. He's a very good manager of people, he keeps it very simple and he keeps the game in perspective."


Stepping off a bus at the Arc De Triomphe on Saturday night felt more like Belfast in the 1970s than Paris in the 21st Century.

On one corner was a large group of armed police officers, on the other was a squad of young soldiers.
There was a khaki-green army pick-up truck beside them, looking totally out of place in a part of Paris associated with tourism rather than terrorism.
A walk down the nearby Avenue des Champs-Ã‰lysÃ©e was eerie.
The normally bustling boulevard was near-deserted. The city felt numb.
It looked like Saturday evening in central Belfast 40 years ago. Empty streets. Shutters down.
On side streets, there were more signs of life. Some people did still want to go out and socialise, just not in the most obvious places.
It was a night when people wanted to keep their heads down.
Indeed, that was the official advice from the authorities with citizens urged to stay indoors with France entering a state of emergency.
In Paris, it seemed everyone had a story to tell, a direct or indirect account of Friday night's sudden attacks.
For young people, social media is usually a vehicle for gossip and humour, but for young Parisians it's now being used for hospital updates and sympathy messages.
A French woman I sat beside on a plane from Dublin to Paris, turned on her phone when we landed at Charles De Gaulle Airport only to find out on Facebook that a friend had died.
Some airlines are offering passengers refunds if they don't want to go to Paris.
Disneyland Paris is closed for three days and some families due to leave Dublin for Disney decided not to go.
Hotels in Paris are doing their best to make life easier for tourists and business workers still staying in the city.
Some hotels are putting on free food and refreshments for guests who are reluctant to venture outside.
At the same time, those wishing to leave early are not having to pay cancellation fees.
Paris wants people to stay. But if they go, the city wants them to come back soon.
Just like London and New York in the wake of mass killings in recent years, Paris will try to slowly recover.
The city's Latin motto is: Fluctuat nec mergitur. The translation is 'tossed by the water but not sunk'.
Already this weekend, you can see the phrase being scrawled on walls.
Yes, Latin graffiti.
Paris is still Paris.


The Chancellor, George Osborne, has announced that the UK will allow Chinese companies to take a stake in British nuclear power plants.

The announcement also said that Chinese firms might eventually be allowed to take majority stakes in British nuclear plants.
Mr Osborne made the announcement on the last day of a trade visit to China.
The first China deal could be as early as next week, with the go ahead for a new Â£14bn plant at the Hinkley C site.
Also on Thursday, a report commissioned for the prime minister warned of a growing risk of power shortages over the next few years.
The Royal Academy of Engineering said the closure of older power plants and the slow progress in building news ones was likely to stretch the system "close to its limits".
Supply is expected to come under strain in the winter of 2014-15.
Most existing coal-fired plants are expected to be closed in 2015 to meet European Union pollution directives, while many gas-fired power plants are not being used at the moment because gas is so expensive.
These would take time and money to bring back on stream.
The Hinkley C project, in Somerset, will be the first new nuclear power station since 1995.
Hinkley C's construction will be led by the French state-controlled giant, EDF, which has been looking for a partner or partners to share the costs.
By Robert PestonBusiness editor
EDF has been negotiating with three Chinese nuclear giants on the Hinkley C project - CGN, CNNC and SNPTC - all of which have been seen by the chancellor this week.
Our business editor, Robert Peston, says he has been told that one or two of these will end up owning perhaps 30% of Hinkley C.
A DECC spokesperson said talks about a contract were underway: "Negotiations remain ongoing between the government and EDF on the potential terms of an investment contract for Hinkley Point C. No agreement has as yet been reached.
"A contract will only be offered if it is value for money, fair and affordable, in line with government policy on no public subsidy for new nuclear and consistent with state-aid rules."
Mr Osborne made the announcement while on a visit to the Taishan nuclear plant in southern China on Thursday which is itself a collaboration between EDF and the China General Nuclear Power Group (CGNPG).
He said: "Today is another demonstration of the next big step in the relationship between Britain and China, the world's oldest civil nuclear power and the world's fastest growing civil nuclear power."
The memorandum of understanding also includes roles for British companies in China's nuclear programme.
China has 17 nuclear reactors in operation, which provide about 1% of its electricity production capacity.
By Damian GrammaticasChina correspondent
In the future, Chinese firms might be allowed more than just minority stakes in UK plants. The government said that "over time, stakes in subsequent new power stations could be majority stakes".
At the weekend, the Energy Minister, Ed Davey, said he believed that a "massive" wave of investment from China, Japan and Korea would secure UK's power supply into the future.
Securing future energy supplies is a major challenge.
A portion of energy bills is being diverted to alternative energy investment in wind farms and solar energy.
But the government believes that renewable energy sources cannot provide enough power for the country's energy needs.
The industry regulator, Ofgem, has also warned of the "unprecedented challenge" to secure power supplies.
It said spare electricity power production capacity could fall to 2% by 2015, increasing the risk of blackouts.


Police in Derry are to review their resources in Galliagh following a rise in anti-social behaviour in the area.

In one case, a young mother said she was "terrified" after her partner was attacked outside their home on Friday.
The police arrested four people, two men and two youths.
"It is cold comfort to the victim, but at times we do have demand and that does affect our response," said PSNI Insp Johnny Hunter.
The attack on the woman's partner happened after he tried to stop a group setting bins on fire, said the woman, who did not want to be named.
"We looked out the window and saw the road on fire," she told Radio Foyle. "The second fellow came over, he lifted a glass bottle off the railings.
"The third time he swung it he let it go and they pulled him (her partner) to the ground as they got into the garden.
"I was standing screaming: 'There's a baby in here, please stop!'
"But they wouldn't listen to me and that's when the neighbours came out," she added.
"When we got into the flat we put the table against the door. I was shaking. I was terrified."
The woman said she, her partner and their two-week-old baby would not return to their home.
The family were also critical of the police response to the attack.
"I can understand from her perspective," said Insp Hunter. "She has suffered a very traumatic and very, very serious incident."
"We will be reviewing that (rise in anti-social behaviour) and we will be reviewing our police deployment in the area."
Police response time suffered in areas where there was an ongoing dissident republican paramilitary threat, said Insp Hunter.
"It's not something for us to hide behind and use as an excuse but there is no doubt that it is a prime consideration when you receive a call," he said.
"Recent instances in Galliagh include a device thrown at police and the find of munitions, so there is no doubt it does affect our response.
"But it's not a reason for us not to respond."


Russian opposition leader Alexei Navalny has been jailed for 15 days for resisting police orders during mass protests on Sunday.

Mr Navalny was among several hundred people who were detained in connection with the rallies across the country.
The court in Moscow earlier fined him the minimum 20,000 roubles ($350) for organising the banned protests.
On Monday the Kremlin accused the opposition of encouraging lawbreaking and provoking violence.
Some young people were paid to attend, a presidential spokesman said.
Mr Navalny later repeated accusations of corruption against Prime Minister Dmitry Medvedev.
The allegations were the main reason behind Sunday's protests, which drew thousands of demonstrators nationwide, including in St Petersburg, Vladivostok, Novosibirsk, Tomsk and several other cities, as well as Moscow.
While Moscow police reported earlier that 500 people had been detained, the OVD-Info human rights group said 1,030 people had been detained in Moscow and that at least 120 of them were still being held.
Perhaps the most striking thing about the protests that swept Russia this weekend was the make-up of the crowd which included significant numbers of young people, even schoolchildren.
The Kremlin's spokesman has criticised organisers for luring them onto the streets, claiming they were paid to turn out. Silent until he spoke, state TV channels have picked up that suggestion and run with it.
But these were young Russians who have grown up under Vladimir Putin on a diet of patriotism. On Sunday, they joined a crowd chanting "Putin - thief" and "Russia will be free!"
Their presence is proof of how effectively Alexei Navalny and his team use social media.
Read more from Sarah: Why Navalny and protesters rattle Kremlin
Mr Navalny appeared in court after being detained on Sunday and spending the night in jail.  Although he escaped a jail sentence on the first charge, he was given 15 days for disobeying a police officer.
Mr Navalny's lawyer, Olga Mikhailova, told Reuters news agency she had expected such a verdict and would appeal against it.
Before his appearance on Monday, Mr Navalny, 40, tweeted from the building: "Hello everyone from Tverskoy Court. The time will come when we will have them on trial (only honestly)."
He argued it was Mr Medvedev who should be summoned as the chief organiser of the protests, because his "corrupt activities led to people coming on to the streets of 99 Russian cities".
Mr Navalny, denying all the charges, said: "They haven't heard witnesses, nor have they satisfied any of our requests. Even the slightest semblance of justice is totally absent here."
He also said again that he plans to run for president in 2018.
Mr Navalny called for the nationwide protests after he published reports claiming that Mr Medvedev controlled mansions, yachts and vineyards - a fortune that suggests income that far outstrips his official salary.
His report, posted on YouTube, has been viewed more than 12 million times.
It includes the accusation that Mr Medvedev had a special house for a duck on one of his properties - and on Sunday, some demonstrators held up images of yellow rubber ducks.
Others showed up with their faces painted green, a reference to a recent attack in which Mr Navalny was hit with green liquid.
Mr Medvedev's spokeswoman called the allegations against him "propagandistic attacks".
Many young people including teenagers took part in Sunday's protests, prompting one report to speak of the rise of the "YouTube generation" as players in the opposition movement.
Alexei Navalny's use of social media symbolises his political style, reaching out to young followers in sharp, punchy language, mocking the establishment loyal to President Vladimir Putin.
An EU spokesman said the Russian police action had "prevented the exercise of basic freedoms of expression, association and peaceful assembly, which are fundamental rights enshrined in the Russian constitution".
The statement added: "We call on the Russian authorities to abide fully by the international commitments it has made... and to release without delay the peaceful demonstrators that have been detained."
US state department spokesman Mark Toner said in a statement: "The Russian people, like people everywhere, deserve a government that supports an open marketplace of ideas, transparent and accountable governance, equal treatment under the law, and the ability to exercise their rights without fear of retribution."
Russian state television completely ignored the protests on Sunday. Monday morning's bulletins were similarly blank.
Pro-Kremlin newspapers also ignored the protests.
But the BBC's Steve Rosenberg in Moscow says there was coverage in some others. Business daily Vedomosti reported a high level of dissatisfaction with the authorities, saying that the young generation had become politicised.
Another paper refers to "Putin's disastrous anniversary" - the protests coming 17 years after the president took office - and says: "A few months ago, Alexei Navalny was seen as yesterday's man who'd missed the bus. He hasn't missed any bus."
The most prominent critic of President Putin, Mr Navalny began his anti-corruption campaign with blogs aimed at state-controlled companies in 2008.
He moved on to opposing the ruling party, United Russia, calling it the "party of crooks and thieves".
He led massive protests following the 2011 election, the biggest in Moscow in December that year, after which he was arrested and jailed for 15 days.
He has said he will run for president in 2018, but a court has convicted him of embezzlement, which would bar him. He denies the charges, calling the case farcical.


A plumber is to face trial accused of causing a gas explosion that destroyed a couple's home and buried them beneath the rubble.

Craig Hall is alleged to have failed to properly install a boiler at Robin and Marion Cunningham's house in Callander, Perthshire, in August 2013.
Prosecutors allege Mr Hall, 34, failed to ensure that a gas pipe was properly supported when he fitted the boiler.
He denies the charge and will stand trial on 2 August.
The alleged incident took place eight months before the explosion.
Mr and Mrs Cunningham were both trapped and had to be freed by fire-fighters.
Nine nearby houses were evacuated and Stirling Council set up a rest centre in Callander as emergency services moved in to make the area safe.
Mr Hall, of Tullibody, Clackmannanshire, denies causing the blast by carrying out the installation of the boiler dangerously and otherwise than in accordance with appropriate standards, contrary to the Gas Safety (Installations and Use) Regulations 1988.
He also denies an alternative charge, under the Health and Safety at Work Act, of failing to take reasonable care for Mr and Mrs Cunningham's safety as a result of his "acts or omissions".


Dani Pedrosa plans to compete in the final MotoGP race of the season in Valencia this weekend, just weeks after he fractured his collarbone, leg and foot in a crash in Japan.

The Repsol Honda rider, 31, was injured in a huge crash during practice for the Japanese Grand Prix.
He said: "These past three weeks haven't been easy because of the pain.
"We're still not sure about how I'll feel on the bike, but I'm happy to be able to get back to racing."
The MotoGP championship was secured by fellow Spaniard and Repsol Honda team-mate Marc Marquez in Japan.
Pedrosa has only won one race all season and is sixth overall.


A doctor and two nurses have appeared in court charged with the manslaughter of a woman who died hours after an abortion in west London.

Aisha Chithira, 32, from Ireland, who was 22 weeks pregnant, died after the procedure at the Marie Stopes clinic in Ealing in January 2012.
Dr Adedayo Adedeji, 63, Gemma Pullen, 32, and Margaret Miller, 54, appeared at Ealing Magistrates' Court earlier.
They were released on bail to appear at the Old Bailey on 3 July.
All three have been charged with manslaughter by gross negligence and "failing to take reasonable care of the health and safety" of Ms Chithira who was affected by their "acts of omission at work".


The fourth of February 2015 marks the third anniversary of the death of Nottingham Forest's former owner and chairman Nigel Doughty.

What he would have thought about the lurid headlines regarding the running of the club this week, it is, frankly, not hard to imagine.
From a position of respect, reliability and repute, Forest have descended into a world of resignations, reprimands and reputational damage.
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While Doughty may not have got everything right, and many disagreed with his decisions, few can doubt that off the field he ran a tight ship, and had Forest operating in a professional, business-like manner.
In a week when Stuart Pearce has also been sacked as manager, Forest look anything but business-like.
Already under a transfer embargo for a breach of the Financial Fair Play guidelines, they now have another, full embargo on them, after failing to pay Peterborough United the latest instalment of Britt Assombalonga's £5m transfer fee.
And while managerial changes do happen from time to time, it is not very often that a chief executive walks out of his post after just five months.
Whether Paul Faulkner's departure was due to the Peterborough situation, the managerial situation, or something else entirely remains to be seen, but at a time when supporters have been clamouring for stability, the opposite appears to be the case at the City Ground.
It was against this backdrop that Dougie Freedman faced the media for the first time as the club's manager on Tuesday and he handled it well.
A measured, balanced, focused yet relaxed approach enabled him to come across as someone with very clear ideas as to what he can do to turn around Forest's fortunes on the pitch.
It seemed a shame that questions had to be asked about the off-the-field issues too.
They distracted attention from Freedman's appointment, and it was certainly a shame that club ambassador John McGovern, who is not involved with financial matters, was the man left to field those questions. Chairman Fawaz Al Hasawi was elsewhere on business.
The Reds turned down significant sums of money for the likes of Michail Antonio and Henri Lansbury towards the end of the transfer window, so the recent problems do not seem to be the result of Mr Al Hasawi having financial problems.
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So, we are left to assume that an error has been made, and the hope from fans will be that the error can be corrected quickly. Paying Peterborough what they are owed will be the first, small step towards restoring the club's reputation before the damage becomes irreparable.
If Dougie Freedman's task is to stabilise things on the pitch, Mr Al Hasawi should be doing the same off it.
He has always said he is at Forest for the long haul and has spoken of the club's great reputation from the past. He is the current custodian of that reputation and says he remains fiercely passionate about restoring it.
To use an on-the-pitch analogy, he may have conceded an own goal or two, but the final whistle has not yet blown. Now is the time for a comeback.


Zambian police have fired tear gas and made 28 arrests during a raid on the home of opposition vice-presidential candidate Geoffrey Bwalya Mwamba.

Officers were looking for people they allege had vandalised election posters and fled to the property.
A police spokesman said petrol bombs were also found, but Mr Mwamba's party has said they were planted.
There have been growing concerns over political violence in Zambia ahead of next month's general election.
The raid comes just two days after a ban on political campaigning in parts of the country had been lifted, reports the BBC's Meluse Kapatamoyo from the capital, Lusaka.
Mr Mwamba, who was not in the house in Kasama in the country's Northern Province at the time, said his grandchildren were injured during the raid.
"My small grandchildren have been taken to hospital as they have been victims of this barbaric act carried out by the police," he said in a post on his Facebook page.
Mr Mwamba is the running mate of Hakainde Hichilema, the presidential candidate of the United Party for National Development (UPND) party.
Northern Province Police Commissioner Bonnie Kapeso said the police officers had to use tear gas in order to get the people they were chasing out of the house.
He added that five petrol bombs were found as well as spears and machetes.
The UPND said in a statement that "the items allegedly found were only recovered once the house was cleared. We know these have been planted".Zambians go to the polls on 11 August to elect a president and a new parliament.
Incumbent President Edgar Lungu, from the Patriotic Front, is facing a tough challenge from Mr Hichilema.


The contenders for the 2016 BBC Sports Personality of the Year will be announced live on The One Show on BBC One from 19:00 GMT on Monday.

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Tennis player Andy Murray won the award last year and in 2013, either side of Formula 1 driver Lewis Hamilton.
The winner will be revealed on 18 December, with tickets for the event at Birmingham's Genting Arena on sale.
The public will be able to vote for their favourite by phone and online during the live show on the night.
Gary Lineker, Clare Balding and Gabby Logan will present the programme from 18:40 GMT on BBC One, with further coverage on BBC Radio 5 live and the BBC Sport website.
The 10 contenders for the Young Sports Personality of the Year were also released on Friday - and the top three will be announced during Blue Peter on 8 December.
"This is an unparalleled era to be competing under the union jack," says BBC chief sports writer Tom Fordyce.
"Sports Personality of the Year? Good luck with whittling it down to the shortlist, let alone choosing your winner."


Portsmouth are in talks with manager Paul Cook to remain with them after he received an offer from Wigan, reports BBC Radio Solent.

Former Latics midfielder Cook, 50, had been keen to talk to Wigan about their managerial vacancy.
Cook moved to Fratton Park from Chesterfield in May 2015 and led Pompey to the League Two title this season.
It is understood any exit would not be linked to Walt Disney chief executive Michael Eisner's takeover of the club.
Graham Barrow has been interim manager of Wigan since March when Warren Joyce left after four months in charge, but could not save them from relegation from the Championship.
Kirkby-born Cook played for Wigan between 1984 and 1988 before a brief loan spell back at the club in the 2001-02 season.


A Kenyan man has been charged with 12 offences including rape, impersonating a gynaecologist and operating a clinic without a licence in Nairobi.

Mugo wa Wairimu pleaded not guilty and has previously denied that he raped his patients after sedating them.
The charges stem from a Kenyan TV report which had footage showing an unidentified man allegedly assaulting an unconscious woman on a clinic bed.
Kenya's Medical Practitioners Board has said he is not a registered doctor.
Mr Wa Wairimu went on the run for a week after the report was aired on Kenya's private Citizen TV.
He was eventually arrested at a hotel outside the capital, Nairobi, after members of the public called the police.
The secretly recorded footage was filmed by a suspicious staff member.
The BBC's Odhiambo Joseph in Nairobi says Mr Wa Wairimu has been in custody since his arrest, as it was argued that releasing him might endanger his life because of the public outrage over the affair.
The court ordered on Friday that he remain in custody until Monday 5 October when his bail application is to be heard.
In one of the last posts on his Facebook page before his arrest, he described the allegations against him as "malicious".
"Mob justice, media or otherwise only replaces due process in failed states. Kenya is not Iraq, Syria or Yugoslavia," wrote Mr Wa Wairimu, who is also a blogger.
He was able to do a few Facebook posts on Friday around the time of the court hearing, reiterating that he was "unbowed" and said "may justice be our shield and defender".


Consultants in England could be offered new NHS contracts within weeks, the BBC understands, after what ministers have called "constructive" negotiations.

Ministers want to remove a clause that lets consultants opt out of providing non-emergency care at weekends as part of their plans for a "seven-day NHS".
A breakthrough is seen as vital by the government as it tries to move on from the junior doctors row.
The latest strike by junior medics ended on Friday morning.
The 48-hour stoppage was the third walkout, with another two planned for next month as the profession fights the imposition of the new contract.
The talks with consultants' leaders at the BMA began in autumn and slowed down at the turn of the year.
However, momentum has gathered in recent weeks, the BBC has been told, and there is a possibility they could conclude before Easter, with meetings held this week and planned for next.
The negotiations, led by NHS Employers for ministers, have centred on removing the weekend opt-out consultants have for non-emergency care.
The government believes this is a major barrier to getting more consultants to work weekends, although the BMA says its research suggests nine in 10 consultants do some level of weekend working.
The opt-out means doctors can command pay three or four times the normal rate when they are asked to do non-emergency weekend shifts. Some of the bonuses consultants get have also been discussed.
Sources close to the talks said there had been "good progress" recently.
But there is concern within the BMA that if consultants do agree a deal it could leave junior doctors isolated, with ministers intent on imposing the contract on them from the summer.
A spokeswoman for the BMA said the talks remained "ongoing" but there had not yet been an agreement.
Any offer would have to be put out to the BMA's consultant membership and consideration is even being given to asking those junior doctors at the end of their training - and therefore close to becoming a consultant - whether they would be happy with the deal.
A Department of Health spokeswoman said: "We want to introduce a fairer contract for consultants that better reflects their role as leaders in our NHS and helps to ensure patients get safe, high-quality care every day of the week.
"Talks with the BMA over proposed amendments to consultant contracts have been constructive."


Former Tottenham, Chelsea and Brentford player Johnny Brooks has died at the age of 84.

An inside forward, Brooks won three international caps for England in 1956, scoring two goals.
After joining from Reading, Brooks scored 51 goals in 179 appearances for Spurs between 1953 and 1959.
Following two years with Chelsea, he joined Brentford in 1961 and helped the Bees win the old Division Four title in 1962-63.
Brooks scored 36 goals in 83 league outings during his stint at Griffin Park before moving to Crystal Palace in 1964.
He helped the Eagles win promotion from Division Three and subsequently had spells in non-league at Stevenage Town and Cambridge City and spent time playing in Canada and North America.
Brooks passed away at a care home in Bournemouth in Tuesday.


Sir Vince Cable is set to become leader of the Liberal Democrats later.

The 74-year old is expected to be the only candidate on the ballot paper when nominations close at 16:00 BST.
Other possible contenders have all ruled themselves out, paving the way for the Twickenham MP and former business secretary to assume the leadership being vacated by Tim Farron.
Sir Vince, who has been acting and deputy leader in the past, has argued that Brexit is not inevitable.
Mr Farron stood down after a disappointing general election in which the party increased its number of MPs from nine to 12 but saw its vote share fall to 7.4%.
The party's main campaign pledge during the election was to give the public the final say on the terms of the UK's exit from the EU in a further referendum, ahead of the scheduled withdrawal date in March 2019.
Although Sir Vince has admitted this message did not "cut through", he has argued that attitudes are beginning to change and that the public mood will come round to the party's position.
He has said the Conservative and Labour leaderships are conspiring to negotiate a "hard Brexit" and he is willing to work with MPs from other parties to thwart this.
Sir Vince, who was knighted last year, is set to be elected unopposed after other potential candidates, including Jo Swinson, Norman Lamb and Sir Ed Davey, said they would not be putting themselves forward.
The veteran politician, who was a Labour councillor in the 1970s before defecting to the SDP and later joining the Liberal Democrats, has never stood for the party's leadership before.
But he has become one of its most recognisable and influential figures, having served as deputy to former leaders Sir Menzies Campbell and Nick Clegg, and been a cabinet minister in the Tory-Lib Dem government for five years.
He will be the oldest leader of the party in its near 30-year history.
He has insisted he has the energy, as well as experience, to lead Lib Dems into the next election, which he believes will happen sooner rather than later.
Mr Farron announced his decision to quit a week after last month's poll, citing the pressures of trying to reconcile his Christian beliefs with his leadership of a progressive political party.
He later revealed that he had decided to step down during the campaign, in which he was forced to clarify on several occasions his views on whether gay sex was a sin or not.


New advice suggests that for a longer life, we need to eat 10 portions of fruit and vegetables a day, but how realistic is this and is it only a diet for the wealthy?

"Healthy foods are three times more expensive calorie-for-calorie than unhealthy foods so there's a very strong price differential in a typical basket," says Anna Taylor,  executive director of the independent think tank Food Foundation.
Vegetables are getting cheaper but, she says, there are people who "haven't got enough money to put food on the table, so for them, trying to secure 10 portions of fruit and veg a day in their diets would be impossible."
The study by Imperial College London, calculated that increasing our fruit and veg intake to 10-a-day could prevent 7.8 million premature deaths each year.
But currently only around a quarter of adults in the UK achieve the five-a-day target.
The British Heart Foundation did a survey which found that a third of UK adults are struggling to afford to eat healthily. So is 10-a-day realistically affordable?
"For some people it is," says Victoria Taylor, senior dietitian at the BHF.
"But for others it would take some serious thought and commitment in terms of working out which fruit and vegetables will be affordable. But it's important to keep in mind that our target is five a day and this study found that the best effects were seen for people who are currently getting below this number.
"The focus on 10 is, in a sense, moving the goalposts and it would be a shame if this put people off aiming for five, or even just having one more portion a day."
The British Dietetic Association says: "What it tells us is that the benefits of eating fruit and vegetables are incremental - in other words eating five portions a day is great, but 10 a day is even better."
So any improvement in your fruit and vegetable intake is a benefit.
Victoria Taylor says cost is not the only reason we don't eat enough fruit and veg.
"There are numerous factors that influence our food choice. Cost is important but so is taste, cooking skills, storage facilities and ability to get to and from the shops.  It's hard to say how much is specifically due to the price of food as all of these issues are interrelated."
The Food Foundation is hosting a conference in June bringing together businesses, farmers, retailers and government departments which aims to make it easier for people to eat vegetables.
Some of the ideas they will be looking at are current pilots in America where if food stamps are spent on fruit and veg, they can be doubled in value so "you create a positive incentive for people to spend their vouchers on fruit and veg because you're giving them more value".
Another scheme sees people who have early stage type 2 diabetes or are pre-diabetic being prescribed fruit and veg and getting vouchers to spend in local markets "to help them rethink their diets and get their diets on track".
We asked BBC readers to send us their questions about the 10-a-day diet and then our health team wrote this piece to try to answer as many as possible.
A lot of people asked about the cost implications of trying to achieve a 10-a-day diet.
Gary asked: "Should fruit and vegetables be heavily subsidized by the government to encourage further consumption?"
Gary explained to us the thinking behind his question:
"Simple consumer habits dictate that people consume more of something when it is cheaper. I believe the same economic principle can be applied to fruit and vegetables. When people go shopping, they have to make the choice of what to buy, and usually, the best value items win."
With concern over the cost of healthy eating, some have asked whether the government should subsidise fruit and veg?
At the moment, the government has "measures in place to support low income families, pregnant women and children under four through Healthy Start Vouchers. These can be spent on milk, fresh or frozen fruit and vegetables."
They also point out that all infant pupils can now get free school meals and they've announced Â£10m funding a year to expand breakfast clubs in up to 1,600 schools.
Currently only 70% of those eligible get the healthy start vouchers and Anne Taylor says the Food Foundation will debate whether that programme should be expanded to include a broader income group or wider age range at its conference. As she points out, this "would create a positive pull of demand - and thereby help to strengthen the British horticulture sector at the same time."
And she thinks in the post-Brexit world there is a big opportunity to help farmers.
"Doesn't it make sense to join up our farming policy with our health policy and think about - could we increase consumer subsidies to really drive up demand so our horticulturalists benefit as well - it's win-win."
"There are lots of different ways we could make it easier to eat veg - which go beyond price and much more about our whole food environment and to what extent fruit and veg is a strong part of that and encouraging us to eat it."
She points out when you look at advertising only "1% of food and soft drink advertising spend goes on fresh veg".
But she believes we need to change our whole way of thinking about fruit and veg and the messages we send - even down to children's TV where, she says, it is "demonised".
"It's set against delicious and junk food or cream cakes, and fruit and veg is the yucky thing that kids don't want to eat. There's a bit of that subliminal stuff that happens in kids' TV because it's funny but it's kind of normalising that this is stuff that you don't want to be eating - so there's a job of work there beyond advertising, in broadcasting to try and not normalise that this is worthy but not tasty."


Sutton United have signed winger Moses Emmanuel following his release by National League rivals Dover on Friday.

Emmanuel scored 11 goals in 36 league games for Dover this season, having signed from Bromley in August.
The 27-year-old also previously had spells with Croydon Athletic, Brentford, Woking and Eastleigh.
Emmanuel is the second former Dover player to sign for Sutton, after striker Ross Lafayette, 30, agreed a move to Gander Green Lane.


Ireland's Olympic golf captain Paul McGinley says Rory McIlroy could have learned from playing in the Rio Games.

McIlroy and US Open runner-up Shane Lowry opted not to compete for Ireland due to fears over the Zika virus, which has links to defects in newborn babies.
"The shame for Rory is I really think he would have benefited from being around other athletes," McGinley said.
With Graeme McDowell also absent, Padraig Harrington and world number 291 Seamus Power will represent Ireland.
Three-time major winner Harrington, 44, and wife Caroline, who have two children, plan to watch as many other sports as possible in Rio after the golf tournament is over.
"It's really good for the heart and the soul to be involved with so many other athletes where it's the most important thing in their game," said McGinley, who captained Europe to Ryder Cup victory over the United States at Gleneagles in 2014.
"I think Padraig is going to come back a better person for it and the Irish team are going to benefit a lot from having Padraig around.
"The Olympics will really stand them in good stead when they come away and back into the golfing environment again, having experienced other sports and seeing how other people approach it and also bouncing ideas off trainers and all kinds of experts who are going to be down there.
"To be part of the biggest sporting event in the world is an opportunity that I'm certainly looking forward to."
World number four McIlroy 27, has spoken about his desire to start a family in the near future, saying: "My health and my family's health comes before everything else.
"Even though the risk of infection from the Zika virus is considered low, it is a risk nonetheless and a risk I am unwilling to take."
Golf is returning to the Olympics after a 112-year absence but three of the world's top four players - Jason Day, Dustin Johnson and McIlroy - plus major winners including Adam Scott and Louis Oosthuizen have chosen not to play.
The Olympics take place from 5 to 21 August.
We've launched a new BBC Sport newsletter, bringing all the best stories, features and video right to your inbox. You can sign up here.


Air and rail traffic has been disrupted in India by dense fog which has enveloped the capital, Delhi, in recent days.

On Wednesday more than 30 flights were either cancelled or diverted, with at least one international flight directed to land in Mumbai.
On Tuesday more than 100 flights were affected as visibility fell to near-zero levels, officials said.
Disruption due to fog in winter has become routine in north India.
Dozens of trains were also delayed by the poor weather.
Fog started to descend on Delhi airport before midnight on Tuesday and thickened early on Wednesday morning, the Press Trust of India (PTI) reported.
Runway visibility dropped to less than 25 metres at the third runway, forcing authorities to suspend operations there, the agency quoted airport sources as saying.
On Wednesday, an Air India flight from Hong Kong was diverted to Mumbai while seven flights were cancelled.
The Meteorological Office says that cold and foggy conditions will continue for the next few days.
Dense fog has also enveloped many parts of the northern states of Rajasthan, Punjab and Haryana, reports said.


Disruption of rail services in and out of London Euston station is expected to continue into the rush-hour after a trackside fire.

Signalling equipment was damaged in the blaze, temporarily cutting Euston's power supply and leading to its evacuation, Network Rail said.
Engineers hope to restore services as soon as possible but delays are likely, after the fire in South Hampstead.
The whole of the West Coast mainline was affected, as far as Liverpool.
Customers on London Midland, Virgin and Southern trains were all disrupted, with services affected at Clapham Junction and Milton Keynes Central.
The fire, which broke out on Wednesday afternoon, also had an impact on a stretch of the London Overground line between Euston and Harrow & Wealdstone.
Network Rail said: "Train customers are impacted in London and the length of the West Coast main line, including Birmingham, Manchester and Liverpool."
It said emergency generators had been brought in to provide temporary power to signals and help get trains moving.
"Engineers are preparing to work through the night to install 100 metres of 11,000-volt power cables, with the aim of getting services back to normal [on Thursday] morning," it added.
Customers on Virgin trains were advised not to travel south of Birmingham.  It said tickets would be accepted for travelling on Thursday or passengers could get a full refund.
Passengers were advised to use services provided by Chiltern Railways, East Midlands Trains and Great Western Railway or check with National Rail Enquiries before travelling.
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Previews and team news for Tuesday's Euro 2016 games, as Northern Ireland bid for a place in the last 16 against Germany.

Northern Ireland v Germany (17:00 BST)
Ukraine v Poland (17:00)
Croatia v Spain (20:00)
Czech Republic v Turkey (20:00)
Create leagues and play against your friends in BBC Sport's new Euro 2016 Predictor game


Amazon is offering other manufacturers free use of its smart speakers' microphone technologies as part of its efforts to spread the use of its Alexa virtual assistant.

The firm will, however, pick and choose who can take advantage of the proposal.
The initiative follows the launch of the Google Home speaker and its associated Assistant.
One expert said the two tech firms were now involved in a "land grab" to become the sector's number one player.
Doing so will help attract developers, and in turn ensure that one product has a wider range of capabilities than the other.
A spokesman for Amazon said the announcement was not meant to signal that it had become less committed to developing its own Echo speaker range, which uses Alexa.
"Our vision is for Alexa to be everywhere, and that means making it available to other companies and services to integrate into a wide range of devices," he explained.
"We expect Alexa to be in many devices over time, including products that compete with Echo, which is why we're investing in making a wide range of hands-free and far-field reference solutions available to OEMs [original equipment manufacturers]."
Amazon's invite-only offer includes:
Those taking advantage of the scheme will be given a reference kit as a starting point for their own designs, and the freedom to source components from a range of parts manufacturers.
Amazon does not reveal sales figures for its Echo devices, but analysts have estimated that more than eight million have been sold in the US alone since their launch in 2014.
The speakers are also available in the UK, Germany and Austria.
Amazon has also formed partnerships with LG, Ford and Huawei, among others, to build Alexa into products including fridges, cars and smartphones.
Google released its rival voice-activated Home speaker last November, which is powered by Google Assistant - a variation of the digital helper it developed for Android handsets.
Many smartphone-makers have since adopted it, and Nvidia has added the tech to its latest TV set-top box.
"Amazon needs to be very careful that it isn't eclipsed by Google," commented Ben Wood from the tech consultancy CCS Insight.
"Google can just roll the Assistant out to hundreds of millions of Android smartphones, so people get it by default, whereas Amazon has to work harder to get Alexa into people's hands or appliances.
"This offer shows Amazon has fully understood the hardware is just a means to an ends and that the real prize is getting people to use its platform, because scale gives such an advantage in this field," he added.


Australia says a piece of debris found on a Mauritian island will be examined to see if it is part of missing Malaysia Airlines flight MH370.

A hotel owner on the island who saw the debris said it bore a design and looked like it was from the inside of a plane.
If confirmed, it would be the first piece of interior debris from the plane yet to be found.
MH370 disappeared in March 2014 while en route from Kuala Lumpur to Beijing, carrying 239 passengers.
Despite an extensive deep water search, led by Australia, the plane and all its passengers remain missing.
Missing Malaysia plane MH370: What we know
MH370 search: Does debris solve the mystery?
Relatives battle for compensation
Australian Transport Minister Darren Chester said the debris, found last week, was an "item of interest".
It was discovered by hotel guests on Rodrigues Island, about 560km (350 miles) east of the main island of Mauritius.
"For sure it looked like part of an aeroplane - it looks like it's from the inside part of it," said William Auguste, owner of the Mourouk Ebony hotel.
"There was wallpaper inside of the plane, you can see this design and part of it is still there."
Last month Australia said debris found in Mozambique was "almost certainly from MH370" and in 2015 French authorities said a wing part found on the Indian Ocean island of Reunion was part of the plane.
The search has focused on the southern Indian Ocean.
More than 95,000 sq km of a 120,000 sq km area has now been examined, with the remainder set to be covered by June, when the search is scheduled to end.


The Sun newspaper's crime reporter was involved in a "corrupt relationship" with a counter-terrorism police officer, the Old Bailey has heard.

Pc Timothy Edwards sold 38 stories and pieces of information to Anthony France over three years and was paid more than Â£20,000, the jury was told.
Mr France, 41, from Watford, denies aiding and abetting a police officer to commit misconduct in public office.
The trial is part of the Metropolitan Police's Operation Elveden.
The operation is investigating alleged illegal payments to police and officials.
Zoe Johnson QC, prosecuting, said Mr Edwards, 49, an officer in the Metropolitan Police's Counter Terrorism Command based at Heathrow Airport, accessed police computer systems and passed on details of "both the victims and perpetrators of crime".
She told the court: "This is not a case of whistle-blowing in a noble cause."
Ms Johnson described Pc Edwards' conduct as an "abuse of power" and asked: "If you were a victim of crime would you expect a police officer to sell your name and address to The Sun?"
Ms Johnson told jurors to "brace" themselves before reading out the first headline of one of the stories allegedly sold by Pc Edwards: "Sexual Healing - BA man quits over squelchy stilettos fetish."
The story, published in July 2008, concerned a BA engineer who was caught on CCTV at Heathrow Airport parading up a makeshift catwalk in high heels, the court heard.
Ms Johnson told the jury that Pc Edwards committed a "grievous abuse" of his power in looking up details of the incident even though no charges were made against the BA employee.
He was paid Â£850 for the story, she said.
In March 2010, Mr France wrote a front page story under the headline, "Heathrow Sex Scandal - Scanner Glamour Ding Dong".
Pc Edwards was allegedly paid Â£1,200 for the story about a member of airport staff abusing his access to new body scanners to "ogle" a female colleague's breasts.
The victim reported the incident to police at Heathrow and days later Pc Edwards read the crime report containing the victim's personal details and her address, the court heard.
One of the journalist's colleagues later called on the victim at home and Ms Johnson said the woman had been "very distressed".
Jurors were told the story turned out to be inaccurate and the Sun printed an apology, also accepting it was an invasion of the victim's privacy.
Mr France is accused of aiding and abetting Pc Edwards to commit misconduct in a public office between March 2008 and July 2011.
The trial continues.