Britain's top anti-terror police chief has tendered his resignation following a security blunder, London Mayor Boris Johnson said on Thursday.

Johnson told BBC radio he had accepted Assistant Metropolitan Police Commissioner Bob Quick's resignation with "great reluctance and sadness," after the blunder triggered premature anti-terror arrests on Wednesday.

"I have this morning with great reluctance and sadness... accepted Bob Quick's resignation as head of counter terrorism," he said, adding that Assistant Commissioner John Yates would take over from him.

Quick was photographed on Wednesday as he arrived at Prime Minister Gordon Brown's Downing Street office for talks on police reform with a sensitive document clearly visible.

It contained details about a planned operation, including that there were 11 suspects — 10 of them of Pakistani origin and in Britain on student visas, and one British born — and where the raids would take place.

Police arrested 12 people in evening raids across northwest England, which media reports said had long been planned but were hastily rescheduled after it emerged the briefing notes detailing the operation were visible in the photo.

Manchester police said several hundred officers were involved in the raids, which saw eight premises searched as part of an ongoing investigation that also reportedly involved the domestic intelligence agency MI5.

The Times newspaper said there were plans to attack a nightclub and shopping centre complex in Manchester, and that the arrests were due to have taken place early on Thursday.

Britain has been on high security alert ever since the July 2005 attacks in London, which killed 56 people including four suicide bombers, and failed car bomb attacks in London and Glasgow in June 2007.

The security threat remains on its second highest level, severe. MI5 chief Jonathan Evans said in January that al-Qaeda leaders based in Pakistan still intended to mount attacks on Britain — and had the capacity to do so.

AFP

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