Two men have gone on trial in the UK for the killing of black teenager Stephen Lawrence in 1993, a case that caused widespread soul-searching in Britain over racism in London's police force.

The suspects, Gary Dobson and David Norris, have denied any role in the stabbing to death of Lawrence in a south London street, and the incident has become one of the most high-profile unsolved murders in Britain.

It was suggested during the investigation of the murder that the attack had a racist motive and Lawrence was killed because he was black.

An official government report in 1999 on the police's handling of the case also found that the force in the capital was "institutionally racist".

Al Jazeera's Laurence Lee reports from London.