He was apparently wearing a backpack - and at least one person said that it was on the front of his torso. He was told to put it on the ground and seemed to be reaching into it when he was shot. Tragic, but how were the officers supposed to know? For all they could have known, the person yelling that he was sick could have been another terrorist trying to distract them. These guys are trained to be professionally paranoid and that, IMHO, is a good thing.    CNN Story