from Schneier on Security by schneier
Some of the confusion generated by Columbine was inevitable: Harris and Klebold started out wearing trench coats, for instance, but at some point removed them, giving the illusion that they were four people rather than two. The homemade pipe bombs they were tossing in all directions—down stairwells, onto the roof—only seemed to further the impression that there were more of them. And then there were the SWAT teams: students trapped inside the building would hear their rifle fire, assume it was the killers and report it to the media by cellphone, complicating the cops' efforts to keep them safe. "This was the first major hostage standoff of the cellphone age," Cullen notes. The police "had never seen anything like it."