London Violence

Riot policeman stand guard in Tottenham, north London, late Saturday, Aug. 6, 2011, after two patrol cars were attacked by members of a community where a young man was shot dead by police on Thursday took to the streets to demand justice. Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission. (AP Photo/PA)

In this image from video, a bus and shop burn in Tottenham, north London late Saturday Aug 6 2011 after two police cars were attacked by members of a community where a young man was shot dead by police on Thursday, took to the streets to demand justice . Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission . (AP Photo/Sky tv via APTN )

In this image from video, a bus and shop burn in Tottenham, north London late Saturday Aug 6 2011 after two police cars were attacked by members of a community where a young man was shot dead by police on Thursday. Several hundred people took to the streets to demand justice . Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission . (AP Photo/Sky tv via APTN )

In this image from video, a bus and shop burn in Tottenham, north London late Saturday Aug 6 2011 after two police cars were attacked by members of a community where a young man was shot dead by police on Thursday. Several hundred people took to the streets to demand justice . Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission . (AP Photo/Sky tv via APTN )

In this image from video, a bus and shop burn in Tottenham, north London late Saturday Aug 6 2011 after two police cars were attacked by members of a community where a young man was shot dead by police on Thursday. Several hundred people took to the streets to demand justice . Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission . (AP Photo/Sky tv via APTN ) UNITED KINGDOM OUT NO SALES TV OUT

The scene in Tottenham, north London late Saturday Aug 6 2011 after two police cars were attacked by members of a community where a young man was shot dead by police on Thursday, took to the streets to demand justice . Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission . (AP Photo/PA)

The scene in Tottenham, north London late Saturday Aug 6 2011 after two police cars were attacked by members of a community where a young man was shot dead by police on Thursday, took to the streets to demand justice . Officers had been attempting to carry out an arrest under the Trident operational command unit, which deals with gun crime in the black community, according to the Independent Police Complaints Commission . (AP Photo/PA)

A police forensic expert searches the scene of a shooting in West Norwood, south London where a 20 year old man was shot dead in the early hours of Saturday morning, Agu. 6, 2011. Three males are believed to have been arrested in connection with the incident, and remain in custody Saturday. (AP Photo / Max Nash, PA)