LONDON, Aug. 16 (Xinhuanet) -- British Home Secretary Charles Clarke has warned terrorists could be planning a third attack on London.

    The warning came after his meeting with the metropolitan police commissioner, Ian Blair, on Monday.

    It would be "absolutely foolish" to assume no more attacks on the capital, and it would be "very surprising" if the July 7 and July 21 attacks were not linked in some way, said the senior official.

    "It is obvious there was a group that worked on July 7 and another group that worked on July 21...The extent to which they had support, training and other assistance from outside is being investigated fully and comprehensively," he said.

    James Hart, the commissioner of the City of London Police, had earlier warned that an attack on the financial center in London was "inevitable."

    Up to 52 people were killed in the first attack by four suicide bombers on July 7.  Several suspects have been arrested since the deadly bombings and the botched July 21 attack. Enditem