The attorney general was delivering a speech to the Federalist Society at a Washington hotel when he started shaking, then collapsed, Associate Attorney General Kevin O'Connor said.
Mukasey was 15 to 20 minutes into a speech about the Bush administration's successes in combating terrorism when he began slurring his words. He collapsed and lost consciousness, said O'Connor, who was traveling at the time and was alerted to what had occurred.
Mukasey's security detail called emergency services. The attorney general was on the stage for 10 minutes being attended to by his FBI detail before medics arrived, according to a Justice Department official.
Mukasey was still breathing at the time, said the official, who spoke on condition of anonymity because she was not authorized to talk to the media.