Sir Paul Condon told a press conference that the bomb was linked to London's two recent blasts targeted at ethnic minorities in Brick Lane and Brixton.

He confirmed it was a nail bomb that ripped through the Admiral Duncan pub on Soho's Old Compton Street.

The police would need "the help of the whole community of London" to catch the bombers. Sir Paul said he was "absolutely determined" that those responsible would be brought to justice.

The bomb is the third nail bomb in London in three weeks

There was no clear indication yet as to who planted the bomb, he said, adding "it is clearly likely to be far-right extremists".

He confirmed that a BBC newsroom received a call on Friday evening saying far-right group the White Wolves had caused the explosion. But the call was described as sounding "garbled", and he said the police were still open minded as to who was responsible.

Sir Paul said the Admiral Duncan pub was visited by police as part of security awareness for "vulnerable communities", including the gay community, this week.

Community spirit

He described the nail bombs as "hate attacks on all of us", and said the whole community of London will have to "work together to defeat those responsible".

"My thoughts tonight are for those who have been killed or injured in this despicable attack," he said.

"It is now a time for calm, vigilance, and for the community to work together to defeat these cowards. Even though the hate is directed at minority communities, its evil affects all of us."

He made a plea for people to not leave bags or packages unattended, and said if anyone saw one they should not touch it, but to ring the police immediately.

He said people concerned for the injured could ring Scotland Yard on 0171 834 7777.