POLICE in the Colorado town where 12 were left dead at a screening of the latest Batman movie were last night preparing to enter the booby-trapped apartment of shooter James Holmes.
Holmes, a seemingly normal PhD student, opened fire in a packed midnight screening of The Dark Knight Rises in Aurora after hurling gas grenades into the cinema. Some victims thought the attack was a stunt for the movie. As well as the dead, Holmes left some 58 wounded.
The gunman apparently told police he was The Joker after his arrest in a nearby car park. The 24-year-old then warned officers that his home was elaborately wired with explosives. Specialist officers spent more than 24 hours at the apartment block before determining that the devices could not be safely defused.
Instead, police put in place a plan to detonate them using a robot and were last night diverting traffic away from nearby streets, having already evacuated neighbouring buildings.
Holmes apparently also set some audio equipment at his apartment on a timer.
The timer was rigged to set off loud music later in the night in an attempt to lure noise-disturbance officers to the home and trigger the explosive devices.
Police have been at the apartment, on the third floor of a red-brick building about four miles from the Aurora cinema where the shooting took place, since before dawn on Friday.
At an earlier press conference, Aurora Police Chief Daniel Oates said: "The pictures are fairly disturbing. It looks very sophisticated, how it's booby-trapped. It could be a very long wait."
Using cameras inserted into the apartment through windows, police and fire officials determined the living room of the apartment was criss-crossed with trip wires connected to a number of plastic bottles containing an undetermined fluid.
Aurora's deputy fire chief, Chris Henderson, said: "To tell you the truth, we don't know how extensive it is. There are several unknown devices along with the litre bottles."
Some of the wounded are believed to have suffered injuries in the immediate chaos that followed the shooting as audience members tried to escape the smoke-filled cinema. Among the wounded, 11 are said to be in a critical condition.
Last night it remained unclear what drove 24-year-old Holmes to commit the atrocity. As officers kept watch at the shooter's block of flats, others visited the relatives of victims killed in the worst mass shooting in the US in recent years, giving families the news of their loved ones.
The dead included 23-year-old Micayla Medek. Anita Busch, the cousin of Medek's father, said: "I hope this evil act, that this evil man doesn't shake people's faith in God."
Among other victims were Alex Sullivan, who was celebrating his 27th birthday; and Jessica Ghawi, an aspiring TV presenter.
Chief Oates said Holmes – who was clad in body black body armour – used a military-style semi-automatic rifle, a shotgun and a pistol that he had bought at local gun shops within the last two months. He also recently purchased 6000 rounds of ammunition over the internet, the chief said.
Near the entrance to the cinema's car park, a makeshift memorial of candles sat in a row alongside piles of flowers. Up the hill, about 20 pastors led a vigil for local people, some hugging and crying. A sign read: "7/20. Gone Not Forgotten".
A federal law enforcement official said Holmes bought a ticket to The Dark Knight Rises and went into the cinema as part of the crowd. He then donned the protective ballistic gear and opened fire.
Authorities said Holmes shot scores of people, picking off victims who tried to flee. At least one person was struck in an adjacent cinema by gunfire that passed through the wall. Adding to the terror and chaos were two gas canisters thrown by the suspect that filled the theatre with smoke.
Tanner Coon, a 17-year-old Aurora resident who was watching the film with two friends, said he first thought the gun shots were firecrackers. When he realised what was happening, he ducked between seats.
When the firing ended, Coon said he started running up the row but slipped in blood and fell on a woman who was lying on the ground. He tried shaking her, he said, but she did not respond, so he left her behind and ran from the theatre.
Within minutes, frantic emergency calls brought some 200 police officers, ambulances and emergency crews to the scene.
The shooting was the deadliest in Colorado since the 1999 attack at Columbine High School in Boulder, less than 20 miles from Aurora, where two students killed 12 classmates and a teacher and wounded 26 others before killing themselves.
HE described himself as quiet and easy-going while fellow students said he was "general pleasant" and a "nice guy".
But the anecdotes emerging of gunman James Holmes as an unobtrusive and unremarkable individual contrast sharply with the actions that left 12 dead and 58 injured.
Fellow students at the University of Colorado said Holmes, a neuroscience graduate who dropped out of his PhD course last month, had few friends and spent much of his time playing the video game Guitar Hero.
Having graduated in 2006 from Westview High School in San Diego, Holmes studied neuroscience at the University of California Riverside, and graduated with honours.
He ran in Westview's cross-country team with Tori Burton, who said: "He was very quiet. He was a nice guy when you did occasionally talk to him. But he was definitely more introverted."
Another classmate, Keith Goodwin, spoke of his shock at seeing the "generally pleasant" young man hit the news for his role in the massacre.
Jackie Mitchell, who lives several blocks from the killer's apartment, said he had drinks with Holmes at a local bar on Tuesday night, and he gave no sign of being distressed or violent.
"We just talked about football," Mr Mitchell said. "He had a backpack and geeky glasses and seemed like a real intelligent guy."
Details of the dead are starting to emerge after police removed the victims' bodies from the cinema in Aurora, Colorado.
Among those named so far is the youngest victim, six-year-old Veronica Moser. Her 25-year-old mother, Ashley Moser, remains in hospital in a critical condition with wounds to her throat and abdomen.
The family of Alex Sullivan said he had also died in the attack, which coincided with his 27th birthday and came before his first wedding anniversary today.
Sullivan's uncle Joe Loewengut said: "He was a very, very good young man. He always had a smile."
Micayla Medek, 23, was also among the dead, her father's cousin, Anita Busch confirmed to reporters.
Jessica Ghawi, a blogger who recently wrote of surviving a Toronto shooting, was also among those killed.
In addition to the 10 people who died at the cinema, two others later died from their injuries.
Matt McQuinn is believed to have died attempting to protect his girlfriend Samantha Yowler as the gunman opened fire. She was wounded and is recovering in hospital, family attorney Robert Scott said.
The family of US serviceman John Larimer said his death was confirmed to them, while 18-year-old AJ Boik also died after going to the cinema with his friend Jordan Crofter, 19, who survived.
gun culture, film violence and killings: the debate rages on
AS the facts surrounding America's latest killing spree are revealed, a revival of the debate regarding the cinema and copycat crime is steadily emerging.
Almost immediately after the shooting at a cinema in Aurora, Colorado, during a screening of The Dark Knight Rises, comparisons were made between James Holmes, the man arrested for the atrocity, and Batman's nemesis The Joker.
Holmes had reportedly dyed his hair red and said something to the effect of "I am the Joker" before releasing two smoke bombs in the cinema.
He was, however, dressed entirely in black – wearing a ballistic helmet, vest, leggings, a throat protector, groin protector, gas mask and black tactical gloves – looking more like Bane, the baddie of the new Batman film.
The latest tragedy has reignited the debate over what prompts such killings: there have already been six mass shootings in the US this year.
Some point to US gun laws, with New York Mayor Michael Bloomberg, calling on Barack Obama and Mitt Romney to address gun control.
The Brady Campaign to Prevent Gun Violence blamed a "national problem of easy availability of guns" in a country where one in four adults owns at least one weapon.
Questions have also arisen over the role cinema plays in influencing individuals to kill.
Scream, the cult horror film, was once described by a US judge as a "very good source to learn how to kill someone" and was cited as the motivation behind the killing of a 15-year-old in Belgium in 2001.
In 2004, Donald Gonzales, 25, claimed Nightmare on Elm Street inspired him to go on a three-day killing rampage in the south of England that left four people dead.
The 1987 Hungerford massacre was linked to the film Rambo and eight murders were blamed on Oliver Stone's 1994 film Natural Born Killers.
Warner Brothers made a nod to the connection by saying it will cut scenes with guns from the trailer of The Dark Knight Rises and cancelling the trailer for upcoming film Gangster Squad due to footage of gunfire in a cinema.
Christopher Nolan, director of the Batman trilogy, released a statement saying cinema is an "innocent and hopeful place" and expressing his sorrow at the tragedy in Aurora.