BBC's Jon Silverman outlines police concerns of racist attacks

Scotland Yard said a "growing number" of threats from extreme right-wing groups had been received since the Brixton bomb.

Metropolitan Police commissioner Sir Paul Condon said catching those responsible for the Brixton attack and Saturday's bomb in Brick Lane was the "major priority" for the force.

Sir Paul Condon: "This device was clearly designed to maim and kill"

He appealed to the public to help police catch those responsible, but warned that people should not touch any suspicious devices.

One of those injured in the Brick Lane explosion is believed to have been taking the device to Brick Lane police station in his car when it went off.

The BBC's Jon Silverman: The police are treating this with the same gravity as the IRA threat

Alan Fry, deputy assistant commissioner, said he was not prepared to give details about the man, but confirmed that he was white.

Police investigating the Brick Lane bombing have found part of a clock at the scene - indicating there may have been a timing device.

It was in a black Reebok sports bag left in Hanbury Street - a few hundred yards from where the bomb exploded.

Officers are sifting through hours of security camera video tape in the hope of finding vital clues.

Commander Mike Craik, commander for the area of east London where the nail bomb exploded, said: "There is lots we can do, we have lots of evidence.

"There are video cameras, we are going through hours and hours of video tape."

The device exploded in an area of Shoreditch, which has a large Bangladeshi community. Six people were hurt, none of them seriously.

Bomb struck heart of Bangladeshi community

Police are linking the explosion with the Brixton nail bomb in south London a week ago and say both attacks were racially motivated.

An extreme right-wing group, Combat 18, has said it carried out the Brick Lane attack. Four racist groups claimed responsibility for the Brixton bombing.

Just metres from where the blast happened, the Brick Lane market opened for business on Sunday.

Increased tension

But many shops remained closed due to damage and it is likely to be days before they can be fully repaired.

Community leaders say there has been increased tension in ethnic minority areas across London in the wake of both the Stephen Lawrence inquiry and last weekend's nail bomb.

They said there has beem concern among ethnic minorities about the likelihood of a prolonged racist bombing campaign.

"I think that there will be a call for the police to step up their efforts to catch the perpetrators. The effect of this will be shock in the community and the terror that has been caused is unacceptable," said Claude Moraes of the Commission for Racial Equality.

• Police are asking witnesses to call the hotline number of 0800 789321.