A video has been released of British police pushing to the ground a man who minutes later died of a heart attack on the eve of last week's G20 summit.
The Independent Police Complaints Commission (IPCC), the UK's police watchdog, now wants to analyse the footage as part of its investigation into Ian Tomlinson's death in London last Wednesday.
In the video, shown on the UK Guardian newspaper's website on Tuesday, Tomlinson, who was walking home from his job as a newspaper vendor, had seemingly strayed into the protest area near the Bank of England, when a group of riot police with dogs tried to corral him forward.
Tomlinson, 47, was walking away from the group in an isolated position, when a policeman approaches him, apparently hits him on the legs with a baton and then shoves him to the ground.
Tomlinson, who had his hands in his pockets and is seen offering no resistance at the time, was flung to the ground, after which bystanders came to his assistance.
Within minutes he had collapsed in a nearby road suffering a heart attack. Police attempted to resuscitate him and he was taken by ambulance to hospital where he was pronounced dead.
The IPCC is now attempting to obtain a copy of the video to determine whether the action by police contributed to the cardiac arrest.
Immediately after the death, police said that they had tried to resuscitate Tomlinson but made no mention of any earlier contact.
Scotland Yard have not been able to comment on the footage due to the IPCC's investigation.
The video was shot by an American fund manager who was witnessing the protests out of curiosity.
About 4,000 anti-capitalist protesters had massed in central London the day before the G20 summit, during which world leaders discussed resolutions to the world economic crisis.
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