Britain's top police officer pledged today that "the other people involved in the murder of Stephen Lawrence should not rest easily in their beds".

Scotland Yard Commissioner Bernard Hogan-Howe welcomed the convictions of David Norris and Gary Dobson for the racist murder.

And he urged people to come forward with more information about the 1993 killing as he hailed Lawrence family members and forensic experts for their work securing Tuesday's guilty verdicts.

In a direct appeal for further potential witnesses, he added: "Anything you know, please tell us... We can make a difference in this case still."

When asked about allegations that the Metropolitan Police was still institutionally racist, Mr Hogan-Howe said: "I hope we are not but it is a bit like asking someone if they are a nice person. Are we the best people to ask?"

He said the force was "hugely different from where we were" at the time of Mr Lawrence's death.