MI5 AND the Metropolitan Police Racial and Violent Crimes Taskforce are investigating the Brixton nail bombing as Scotland Yard becomes increasingly convinced that the bomber was racially motivated.
Detectives investigating the explosion, which hit a busy shopping market in south London last Saturday injuring 39 people, are pursuing the theory that the bomber is a renegade member of a far-right organisation with a racist grudge.
At a briefing yesterday, Detective Chief Superintendent John Bunn, of Scotland Yard's anti-terrorist branch, said the racial motive was a "very, very serious line of inquiry".
He said: "We are looking at the possibility that it was white racist thugs who committed this brutal crime."
It was revealed that three more extreme right-wing "groups" have claimed responsibility for the attack, following an earlier claim purporting to come from neo-Nazi thugs Combat 18.
The claims included one from someone using the name White Wolf, who has a long history of writing hate mail to black groups and recently sent a vitriolic circular to black MPs. Another claim was made by a group called the English National Party.
None of the claimants has given any specific information which would corroborate their involvement.
Mr Bunn confirmed yesterday that MI5 and Commander John Grieve, the head of the Racial and Violent Crimes Taskforce and the man investigating the racist murder of Stephen Lawrence, were participating in the bomb investigation.
Police are still looking at the claim said to have been made by Combat 18. Mr Bunn said: "That line of inquiry is being investigated very thoroughly and looked at in meticulous detail."
Combat 18 has been under such heavy police surveillance in recent months that experts believe it would have been difficult for it to carry out the attack.
Detectives have not ruled out the possible significance of a broken-down 159 bus which had stalled close to where the bomb went off. Mr Bunn said it was conceivable that Brixton was not the bomber's target. "There is the possibility the bomber got off that bus and was on his way somewhere else," he said.
A pounds 30,000 reward has been offered for anyone with information leading to the arrest and conviction of suspects.
Police will today stage a reconstruction at the scene of the bomb. Officers will seek to trace new witnesses - particularly those who only use the market at weekends.
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