The man in custody for allegedly killing 12 people at the screening of the latest Batman movie in Aurora, Colorado told authorities after the shooting that he "was The Joker," NYPD police commissioner Ray Kelly said today.
Kelly told reporters the suspect, identified by federal officials as 24-year-old James Holmes, had dyed his hair like The Joker. The Joker is a well-known villain in the fictional Batman universe. The attack took place at a screening of "The Dark Knight Rises," the final movie in a Batman trilogy, following "The Dark Knight" in which The Joker was the principal villain.
Two federal law enforcement officials confirmed the details of The Joker costume to ABC News. Police said the weapons used in the massacre include a military-style AR-15 assault rifle, a shotgun and two handguns.
Witnesses to the shooting said that a man appeared at the front of the theater about 20 minutes into the movie with a rifle, handgun and gas mask. He then threw a canister that released some kind of gas, after which a hissing sound ensued, and he then opened fire on the crowd packed into the early-morning screening of the film.
"We were maybe 20 or 30 minutes into the movie and all you hear, first you smell smoke, everybody thought it was fireworks or something like that, and then you just see people dropping and the gunshots are constant," witness Christ Jones told ABC's Denver affiliate KMGH. "I heard at least 20 to 30 rounds within that minute or two."
A man who talked to a couple who was inside the theater told ABC News, "They got up and they started to run through the emergency exit, and that when she turned around, she said all she saw was the guy slowly making his way up the stairs and just firing at people, just picking random people."
"The gunshot continued to go on and on and then after we didn't hear anything," the couple told the man. "We finally got up and there was people bleeding, there was people obviously may have been actually dead or anything, and we just ran up out of there, there was chaos everywhere."
The FBI said approximately 100 of its agents are on the scene assisting with the ongoing investigation.
ABC News' Lee Ferran, Jason Ryan, Clayton Sandell, Kevin Dolack and Collen Curry contributed to this report.