A total of 71 people were shot in Friday's rampage at a cinema in the Denver suburb of Aurora that has left 12 people dead, the local police chief said.
At a press conference, Aurora Police Chief Dan Oates said the first calls to police came at 12:39am and within a minute they were receiving hundreds of 911 calls.
Police arrived on the scene within about a minute after the first distress call, and took the suspect, James Eagen Holmes, into custody shortly thereafter.
Oates added that Holmes, who police think acted alone, was wearing extensive body armour and had three firearms when he was arrested. He had left one gun behind in the theatre.