Scotland Yard will undertake an internal review of hundreds of hours of police footage recorded of clashes during the G20 protests in London to identify if any further incidents require investigation.

Commissioner Sir Paul Stephenson said officers will look for any further matters that "warrant investigation" as trouble flared between demonstrators and police.

The senior officer also called in Government inspectors to review controversial public order policing tactics, including the "kettling" of large groups for long periods of time.

Her Majesty's Chief Inspector of Constabulary, Denis O'Connor, will lead the review of tactics which have been fiercely criticised in the aftermath of the protests.

Sir Paul also said officers must always display shoulder identification numbers after claims two suspended territorial support group officers were not wearing them.

Earlier, the family of a protester who was slapped across the face by a police officer during the G20 demo revealed she has been left "traumatised".

The unidentified Brighton woman, named only as Nicky, has been thrust into the spotlight after amateur footage of the confrontation outside the Bank of England emerged online.

The Metropolitan Police suspended the territorial support group officer on Tuesday night after a video of the incident was posted on YouTube. Another officer from the unit has already been suspended over the death of newspaper seller Ian Tomlinson, who died from a heart attack minutes after being hit with a baton and shoved to the ground.