Police will launch a fresh appeal for witnesses to the murder of Stephen Lawrence 20 years since the attack on Crimewatch tonight.
Stephen was stabbed to death by a group of up to six white youths in an unprovoked racist attack as he waited at a bus stop in Eltham, south-east London in 1993.
Gary Dobson and David Norris were convicted of his murder last year and jailed for life after a forensic review of the case found significant new scientific evidence on clothing seized from their homes. But the case remains open.
Police hope that by walking viewers through the events again they may persuade witnesses to come forward.
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