Batman massacre gunman James Holmes yesterday appeared in court in Colorado sporting bright orange dyed hair, reminiscent of Batman’s biggest enemy, the Joker.

Mr Holmes sat wide-eyed and appeared dazed as the judge in Denver advised him of his legal rights prior to his being charged next Monday with the murders of 12 people at the Batman film premiere.

The 24-year-old former graduate student who has been held in solitary confinement since Friday, is refusing to cooperate with police, and it could take months to learn what prompted his attack on moviegoers at the Friday midnight screening.

Investigators found a Batman mask inside Mr Holmes’s booby-trapped apartment.

During the attack, he set off gas canisters and used a semi-automatic rifle, a shotgun and a pistol.