National debate urged over police

Nick Hardwick, chairman of the Independent Police Complaints Commission, said he had "serious concerns" about front-line supervision of officers at this month's demonstrations, adding that police need to remember they are "servants, not masters" of the people.

The commission is already investigating events leading up the death of newspaper seller Ian Tomlinson on April 1, and an allegation of an assault on Nicola Fisher at a vigil for Mr Tomlinson on April 2.

The comments come as the IPCC launches its third investigation into tactics at the G20 protests after a London man claimed he was assaulted by an officer.

All three complaint probes arose after footage of police clashing with the people concerned were broadcast.

Mr Hardwick welcomed an inquiry into policing at the G20 protests announced last week by the police inspectorate, telling The Observer: "It's got to be a democratic political question about how do we want to be policed? I think that needs a proper parliamentary discussion."

He raised concerns about incidents of officers disguising or removing their identity numbers - as pictured in several publications this week.

The latest IPCC probe surrounds the unnamed man's claim that he was assaulted at a police cordon on Cornhill in the City of London some time between 6pm and 7pm on April 1.

An IPCC spokesman said more than 185 complaints had been received relating to G20 of which almost 90 were from alleged victims of - or witnesses to - excessive police force. A further 52 relate to complaints about police tactics such as not letting people through an area.

A Scotland Yard spokesman said the force was co-operating fully with the IPCC and would "proactively" give it any relevant information.