, AURORA, Jul 21 – Police on Saturday studied ways to enter an apartment rigged with explosives belonging to the man believed to have killed 12 moviegoers at an opening of the latest Batman movie.
Bomb squad experts had been trying for about 24 hours to enter the apartment since shortly after the suspect, 24 year-old James Holmes, allegedly entered a packed cinema early on Friday showing the “The Dark Knight Rises” and opened fire.
Twelve people were killed by the hail of gunshots, and 58 others wounded.
Hundreds of mourners held candles late on Friday, many sobbing and hugging each other in an outpouring of grief for those who died in the rampage in Aurora, a town in the US state of Colorado.
The shooting drew expressions of concern from political leaders led by President Barack Obama, and revived the perennial debate about gun control in the United States.
On Saturday, Obama promised justice to the residents of Aurora, saying: “The federal government stands ready to do everything necessary to bring whoever’s responsible for this heinous crime to justice.”
He said the government “will take every step possible” to ensure the safety of all Americans.
The apartment could reveal clues about the 24-year-old gunman’s motive.
Aurora police chief Dan Oates described the challenge of entering the home safely.
“I personally have never seen anything like what the pictures show us is in there,” Oates said. “I see an awful lot of wires, trip wires, jars full of ammunition, jars full of liquid. Some things that look like mortar rounds.”
Late on Friday the town gathered for two vigils as it emerged that Holmes bought more than 6,000 rounds of ammunition on the Internet, and four guns, in the two months before the rampage.
“In the last 60 days, he purchased four guns at local metro gun shops and through the internet he purchased over 6,000 rounds of ammunition,” the police chief said.
He added: “My understanding is that all the weapons that he possessed he possessed legally, and all the clips that he possessed, he possessed legally, and all the ammunition he possessed, he possessed legally.”
The masked, black-clad shooter burst into the movie theatre barely 20 minutes into the midnight screening early on Friday, throwing two tear-gas type devices before opening fire.
“As far as we know, it was a pretty rapid pace of fire in that theatre,” said Oates, his voice at times cracking with emotion.
In an end-of-day update, he slightly amended the number of victims from 71 to 70. Twelve of them died, including 10 in the theatre.
A local children’s hospital reported six young victims, the youngest of whom was aged only six. At least three of the wounded were US military members, the Pentagon said.
Shots fired in one auditorium went through the wall and hit people in the auditorium next door. The first police officers were on the scene within 90 seconds, while eventually some 200 swarmed around the building.
Police arrested Holmes – who was wearing full body armour and a gas mask, apparently to protect him from effects of his own tear gas – without encountering resistance by his car at the rear of the theatre.
Holmes, who reportedly attended the University of Colorado medical school until last month, had no criminal record aside from a citation for speeding in October 2011, according to police.
Witnesses described chaos chillingly similar to that depicted in the Batman films, in which maniacal villains terrorize Gotham City.
“I saw some people start to get up. I poked my head up to see what was going on and when I did that I saw another flash and instantly put my head down as he started shooting again,” said 17-year-old Tanner Coon.
Cinemas in New York tightened security at Batman showings, and the AMC theatre chain announced a ban on face masks and fake weapons – several people wore costumes in Aurora, possibly helping Holmes to blend in with the melee.
The French premiere of the film in Paris was cancelled.
As with previous such shootings, lobby groups and some political leaders called for legislation to restrict civilians’ access to firearms.
“Maybe it’s time that the two people who want to be president of the United States stand up and tell us what they are going to do because this is obviously a problem across the country,” New York mayor Michael Bloomberg said.
Aurora is 20 miles (32 kilometres) from the scene of the 1999 Columbine High School massacre, in which two students shot dead 13 people before committing suicide.