Watch video of the Ian Tomlinson assault

The man who died during the G20 protests in London last week was violently pushed from behind by a riot policeman, a dramatic new video shows.

The sequence clearly identifies Ian Tomlinson, 47, walking in front of a group of officers, some with dogs and others in riot gear, with his hands in his pockets. When he does not move out of their way an officer pushes him violently from behind, sending him to the ground. In slowed-down footage, an officer wearing a helmet can be seen apparently hitting Mr Tomlinson from behind with a baton on the leg.

Police then stand watching as passers-by go to help Mr Tomlinson while he sits on the floor, apparently remonstrating with the officers.

A few seconds later he is seen walking away. A source involved in the inquiry told The Times: “Your stomach does take a bit of a turn when you watch what happened.”

The officers involved in the incident will be tracked down and spoken to today by Independent Police Complaints Commission investigators.

A post-mortem examination last week found that Mr Tomlinson, who was thought to be returning home from working in a newsagents when he got caught up in the demonstrations, died from a heart attack.

The Times was told yesterday that he did not have any bruises or scratches on his head or shoulders that would indicate police brutality.

The video, which lasts for a couple of minutes, will now form the basis of an investigation into his death by the IPCC. A spokeswoman for the commission said it had been made aware of the video, posted on The Guardian's website. “We are now attempting to recover this evidence. We will be assessing this along with the other statements and photographs that have already been submitted,” she said.

The footage, shot at about 7.20pm at Royal Exchange Passage in Central London, was reportedly taken by a fund manager from New York who was in London on business last Wednesday. He told The Guardian: “The primary reason for me coming forward is because it was clear the family were not getting any answers.”

Deborah Glass, of the commission, said last night: “Initially, we had accounts from independent witnesses who were on Cornhill [a street adjoining the passage in which the footage was shot] who told us that there had been no contact between the police and Mr Tomlinson when he collapsed.

“However, other witnesses who saw him in the Royal Exchange area have since told us that Mr Tomlinson did have contact with police officers.

“This would have been a few minutes before he collapsed. It is important that we are able to establish as far as possible whether that contact had anything to do with his death.”

Anna Branthwaite, a photographer, has already given a detailed statement to City of London Police in which she described how Mr Tomlinson was rushed from behind and hit with a police baton. She said: “I saw a riot police officer rushing towards him from behind and grabbing hold of him from behind and charging with him. He [the officer] grabbed him by the scruff of the neck and used his own body to propel him forward.”

A statement by another witness, who did not wish to be named, says that Mr Tomlinson was pushed from behind and fell forward on his head.

Mr Tomlinson's family appealed yesterday for more witnesses who saw him collapse to assist efforts to establish the cause of his death.

They said: “Ian was a massive football fan and would have looked distinctive in his Millwall top.” They asked for anyone who saw Mr Tomlinson in Royal Exchange Square to contact the IPCC. They added: “We also want to clarify that Ian was not a protester.”

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