Police says bombers could strike London again

London police chief Sir Ian Blair said Thursday that bombers still at large following the failed July 21 attacks could strike again. He also warned that other terror cells could be capable of launching attacks.

"It does remain possible that those at large will strike again. It does also remain possible that there are other cells who are capable and intent on striking again," Blair said at a meeting of the Metropolitan Police authority.

Blair said the failed July 21 attacks, which came two weeks after 52 people were killed by four men who blew themselves up on three subway trains and a bus, was not a sign the terrorists had been weakened in any way.

"This is not the B team. These weren't the amateurs. They made a mistake. They only made one mistake, and we're very, very lucky," he was quoted as saying by the AP.

Blair said he was confident that police would find the bombers - as well as whoever backed them.

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