Lawrence police: Murder weapon believed found

Police hunting the killers of Stephen Lawrence are to carry out forensic tests on what they believe is the murder weapon - a 2ft knife - it was revealed last night. DNA tests are also to be carried out on a coat found near the murder scene in south-east London seven years ago.

In addition, Scotland Yard has published a photofit of a blond-haired witness who was walking in front of the black teenager moments before he was stabbed to death by a racist gang. Police say they know who the witness is but the person has refused to give evidence so far. They also said several new witnesses to the stabbing had come forward.

The dramatic new developments were revealed last night on BBC TV's Crimewatch UK programme in which Stephen's mother said Scotland yard had told her one of the killers had confessed to his girlfriend about the murder. Doreen Lawrence appealed to the woman to help the murder inquiry.

No one has been convicted of killing 18-year-old Stephen. At the Old Bailey in 1996, Neil Acourt, Gary Dobson and Luke Knight were cleared of his murder. Legal proceedings against two other men, Jamie Acourt and David Norris, were dropped at an early stage.

Mrs Lawrence asked the friends and family of the killers to come forward. "We are appealing to the mothers, the girlfriends and boys at the time who would have heard something. The boys would have fully confessed to them," she said. "There's one particular girl, who I understand had heard the confession from one of them..."

The Deputy Assistant Commissioner, John Grieve, the officer in charge of the murder case, revealed a map on last night's programme of the movements of suspects and witnesses at the time of the murder. "New witnesses have already come forward and the map will be used to appeal to a very specific, important witness, who has never made a statement," he said. "It's been seven years since the murder of Stephen Lawrence and we are now using up-to-date techniques to record the movements of witnesses and suspects on the night."

Mr Grieve and his team are hoping that former friends and acquaintances of the killers will no longer be held back by fear or loyalty to the murderers from helping the police.

On the programme, Neville Lawrence, Stephen's father, aid: "We know that these people [the suspected killers] were involved in other crimes from schools days. They have committed a lot of crimes in the past. The one with Steven was just one of the crimes they were involved in."

Among the suspects being kept under surveillance is one said to be a blond youth, described by witnesses who saw a gang around Stephen and his friend, Duwayne Brooks, that night in Eltham

Yesterday's developments came as Mr Brooks, 23, was cleared in court of charges of indecent assault after a judge ruled he would not have a fair trial following a "series of errors and misjudgements" by the prosecution.

The case against him collapsed at the Old Bailey after it was alleged that the "lay advisor" appointed to liaise between the alleged victim and police had acted improperly. Ironically, the use of civilian police mediators in racially sensitive cases was one the recommendations made in the Macpherson report into Stephen's death.