Aurora, Colorado police said the movie theater shooter, 24-year-old James Holmes acted alone. He was a medical student in the process of withdrawing from a doctoral program at the University of Colorado medical school.
When Holmes was apprehended he told police he was "the Joker." Who is this lone gunman?
Gunman turns Batman screening into real-life "horror film"
The man suspected of shooting up an Aurora, Colorado, movie theater screening the new Batman film early Friday, killing 12 and wounding 59, also left his apartment rigged with traps, police said.
"It's booby trapped with various incendiary and chemical devices and trip wires," Aurora Police Chief Dan Oates said, adding that it could take days to work through the apartment safely.
Five buildings around suspect James E. Holmes' Aurora apartment were evacuated, Oates said.