New York City's police commissioner says the gunman in the Colorado movie theatre rampage had painted his hair red and called himself the Joker - the villain from the Batman movies.
The suspected gunman, identified as James Holmes, a 24-year-old doctoral student in neuroscience who was about to drop out of the University of Colorado-Denver, was arrested near a car behind the theatre.
Authorities gave no motive for the attack. The FBI said there was no indication of ties to any terrorist groups.
Coming up: First pics: Shootout at Batman screening in Denver