The reclusive drop-out PhD student behind the Dark Knight screening shooting spree said he was ‘The Joker’ after he carried out his horrific attack, it has been revealed. James Holmes, 24, had painted his hair red to resemble Batman’s arch nemesis before firing into the crowded theatre in Aurora, Colorado, according to New York Police Commissioner Ray Kelly. ‘It clearly looks like a deranged individual,’ Kelly said of the shooter at a news conference, CBS reported.‘He had his hair painted red. He said he was “The Joker”, obviously the enemy of Batman.’ A neighbour also reported that police, who were searching Holmes’s apartment for explosives, asked him if he had seen ‘a white guy with crazy hair, possibly dyed unnatural colors’, the Denver Post said. It has also emerged that Holmes, who is accused of killing 12 and injuring 59 after buying a ticket to the film, had been studying at the University of Colorado’s medical campus until June this year. But neighbours at university housing in Denver described Holmes as a recluse who kept himself to himself. One student said: ‘No one knew him. No one.’ Holmes – who had been working towards his PhD for a year before dropping out – had one song blaring from his stereo in the hours before the massacre and left the music on repeat in his booby-trapped apartment as he departed to commit the massacre.  His shocked mother confirmed that he was behind the massacre, telling reporters: ‘You’ve got the right man.’ A federal law enforcement official told the Associated Press that Holmes had bought a ticket to the midnight showing and went in to the screen as part of the crowd. He then propped open an exit door as the movie played and put on donned protective a ballistic helmet, vest, throat protector, gas mask, black tactical gloves. Witnesses said he threw a smoke grenade and waited for it to explode before opening random fire with an AR-15 assault rifle, a Remmington 12-guage shotgun and a 40-caliber Glock handgun. He also had another 40-caliber Glock in his car, police said. Twelve people died in the horrific attack, and the bodies of 10 victims are still inside the theatre, police said. The youngest victim is believed to be just 12. Scores of injured victims are now fighting for their lives; the youngest is just three months old, and is believed to have been shot at blank point range in the back.  Holmes was arrested in the cinema parking lot where he did not put up any resistance. He told police he had explosives at his North Aurora home, and they closed off the apartment to search. In an address today, President Obama said he was ‘heartbroken’ to hear of the ‘heinous’ crime. ‘Such violence, such evil is senseless. It’s beyond reason,’ he said. ‘But while we never fully know what causes someone to take the life of another, we do know what makes life worth living. ‘What matters, at the end of the day, is not the small things, the trivial things that so often consume us in our daily lives. Ultimately, it’s how we choose to treat one another, how we love one another.’ He added that if anything can be taken away from the tragedy, ‘it reminds us that life is very fragile’.