United States president Barack Obama will travel to Colorado on Sunday (local time) to visit with families of victims of the Aurora movie theatre shooting.
White House communications director Dan Pfeiffer announced plans for the trip today. Aides said the trip would also include meetings with state and local officials.
In his weekly radio address, Obama called for prayer and reflection on the shooting rampage in Aurora, which left 12 dead and 58 injured. He urged Americans to embrace the families who lost loved ones in Aurora and to "let them know we will be there for them as a nation."
Meanwhile, the suspect in the shooting planned his rampage with "calculation and deliberation," police said.
James Holmes, 24, received deliveries for months which authorities believe armed him for battle and were used to rig his apartment with dozens of bombs.
Authorities were still working to clear dangerous explosive materials from inside Holmes' suburban Denver apartment a day after police said he opened fire and set off gas canisters in a suburban theatre minutes into the premiere of the Batman film The Dark Knight Rises.
His apartment was rigged with jars of liquids, explosives and chemicals that were booby trapped to kill "whoever entered it," Aurora Police Chief Dan Oates said, noting it would have likely been one of his officers.
"You think we're angry? We sure as hell are angry," Oates said.
Authorities wouldn't discuss a motive for one of the deadliest mass shootings in recent US history, as makeshift memorials for the victims sprang up and relatives began to publicly mourn their loved ones.
Holmes had recently withdrawn from a competitive graduate program in neuroscience; neighbours and former classmates in California have said he was a smart loner who said little.
He apparently had prepared the attack at the Aurora theatre well in advance, receiving multiple deliveries by mail for four months to his home and school and buying thousands rounds of ammunition on the internet, Oates said.
"He had a high volume of deliveries," Oates said. "We think this explains how he got his hands on the magazine, ammunition," he said, as well as the rigged explosives in his apartment.
"What we're seeing here is evidence of some calculation and deliberation," Oates added.
ROBOT USED TO TAKE DOWN TRIP WIRE
Federal authorities detonated one small explosive and disarmed others inside Holmes' apartment after sending in a robot to take down a trip wire, FBI Special agent James Yacone said.
Bomb technicians then neutralised what he called a "hyperbolic mixture" and an improvised explosive device containing an unknown substance. There also were multiple containers of accelerants, he said.
"It was an extremely dangerous environment," Yacone said, saying anyone who walked in would have sustained "significant injuries" or been killed.
Outside the apartment, police arranged plastic storage boxes and large white plastic bags, possibly for evidence, although no officials were available to confirm the purpose of the containers.
Holmes was in solitary confinement for his protection at a county detention facility, held without bond on suspicion of multiple counts of first-degree murder. He was set for an initial hearing on Monday (Tuesday NZT) and had been appointed a public defender, authorities said.
Stories of the dead began to emerge, including that of a 6-year-old girl and a man who died on his 27th birthday and a day before his anniversary. Families grieved and waited at hospitals, which reported at least seven wounded still in critical condition Saturday and others with injuries that likely are permanent.
Veronica Moser, 6, had gone to the movies with her mother, who was drifting in and out of consciousness in a hospital intensive care unit, bullets lodged in her throat and a gunshot wound to her abdomen.
"Nobody can tell her about it," Annie Dalton said of her niece, Ashley Moser. "She is in critical condition, but all she's asking about is her daughter."
Veronica had just started swimming lessons on Tuesday, Dalton said.
"She was excited about life as she should be. She's a 6-year-old girl," her great aunt said.
Another victim, 27-year-old Matt McQuinn, was killed after diving in front of his girlfriend and her older brother to shield them from the gunfire, said his family's attorney, Rob Scott of Dayton, Ohio.
Alex Sullivan had planned a weekend of fun, first ringing in his 27th birthday with friends at the special midnight showing of The Dark Knight Rises and then celebrating his first wedding anniversary on Sunday.
"He was a very, very good young man," said Sullivan's uncle, Joe Loewenguth. "He always had a smile, always made you laugh. He had a little bit of comic in him."
6000 ROUNDS OF AMMUNITION PURCHASED
Oates said Holmes used a military-style semi-automatic rifle, a shotgun and a pistol to open fire on the unsuspecting theatre-goers. He had bought the weapons at local gun stores within the last two months. He recently purchased 6000 rounds of ammunition over the internet, the chief said.
Holmes also bought an urban assault vest, two magazine holders and a knife for just over US$300 on July 2 from an online supplier of tactical gear for police and military personnel, according to the company.
Chad Weinman, CEO of TacticalGear.com, said his company processes thousands of orders each day, and there was nothing unusual in the one that Holmes placed.
While his company often receives orders from military units and law enforcement organizations, it is not out of the ordinary for individual police officers or soldiers to place orders, he said.
"Everything Mr. Holmes purchased on July 2 is commercially available," Weinman said, adding he was "appalled" that the material was sold to Holmes before the shooting.
It wasn't known why the suspect chose a movie theatre to stage the assault, or whether he intended some twisted, symbolic link to the film's violent scenes.
The Batman movie, the last in the trilogy starring Christian Bale, opened worldwide Friday with midnight showings in the US.
The Dark Knight Rises earned US$30.6 million in Friday morning midnight screenings, and, according to industry estimates, roughly US$75-77 million on the day. That put it on track for a weekend total of around US$165 million, which would be the second highest opening weekend ever, following The Avengers.
Warner Bros has announced it would forgo the usual revenue reports until Monday out of respect for the victims.
Sony, Disney and Universal also said they would delay reporting box office receipts until Monday (Tuesday NZT), a day later than the routine Sunday releases for Hollywood.
SUSPECT BOUGHT TICKET TO MOVIE
After buying a ticket to the movie, Holmes went into the theatre and propped open an exit door several minutes into the film, a federal law enforcement official said.
The suspect then returned in protective gear and with high-powered weapons and opened fire, shooting scores of people and picking off victims who tried to flee, officials said.
The shooting was the worst in the US since the November 5, 2009, attack at Fort Hood, Texas. An Army psychiatrist was charged with killing 13 soldiers and civilians and wounding more than two dozen others. It was the deadliest in Colorado since the 1999 attack at Columbine High School, where two students killed 12 classmates and a teacher and wounded 26 others before killing themselves.
HOLMES STUDIED MENTAL DISORDERS
After excelling at the University of California-Riverside, Holmes was in the process of withdrawing from a neuroscience PhD program at the University of Colorado-Denver for unknown reasons.
First-year students must take a three-part exam at the end of the academic year to move on in the program, University spokeswoman Jacque Montgomery said Saturday. Montgomery did not know whether Holmes had taken the exam.
As part of the program, Holmes had been listed as making a presentation in May about Micro RNA Biomarkers in a class named "Biological Basis of Psychiatric and Neurological Disorders."
Mary Muscari, a criminology professor at Regis University in Denver who studies mass killings, said she was not surprised Holmes was studying neuroscience and mental disorders.
"It could be he was interested in that because he knows there's something different in him," said Muscari.
She said that several mass murderers are young men in late adolescent or early adulthood. "We're talking about guys when they're at that age when they're testosterone charged, their brains start developing, and it's also when schizophrenia kicks in."
Those who knew Holmes described him as a shy, intelligent person raised in California by parents who were active in their well-to-do suburban San Diego neighbourhood. Holmes played soccer at Westview High School and ran cross-country before going to college.
Police said they would begin collecting the personal items left by panicked moviegoers in days and would move out of the theatre by midweek. Shaken law enforcement officials urged residents to not stay home.
"I just don't want the shameless and senseless act of one man to make this difficult for families to move on," Aurora Fire Chief Mike Garcia said. "Go out. See a movie. Go out into your city. Don't be afraid."