Capital City police officer Niaz Siddique told reporters that the FBI and other US agencies were assisting the Karachi police in the probe into the bombing which came just before President George W Bush's visit to Pakistan.
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The US investigators visited the site where the explosion has left a 15 ft wide and over 3 ft deep crater and also interviewed several witnesses. They also collected forensic evidence. An 11-member team of Pakistan agency FIA was also helping them, reports said. A DNA test of the bomber was also being carried out, they said. Siddiqui said investigators were preparing a sketch of the bomber based on surveillance camera images from the consulate and neighbouring Marriott Hotel as well as eyewitness accounts. Interior Minister Aftab Khan Sherpao said it was "well planned attack".
"The Rangers tried to stop the car of the suicide attacker, but it broke the suicide barrier and hit the armoured vehicle of the US diplomat killing him and his driver," he was quoted as saying. Meanwhile, the State Department identified the American diplomat kiled in the blast as David Foy, a Foreign Service Officer. His driver Iftikhar Ahmed, a local employee of the consulate, was also killed in the bombing.