AURORA, Colo. — The Colorado shooting suspect planned the rampage that killed 12 midnight moviegoers with "calculation and deliberation," police said Saturday, receiving deliveries for months that authorities believe armed him for battle and were used to rig his apartment with dozens of bombs.
Authorities on Saturday were still working to clear dangerous explosive materials from inside James Holmes' suburban Denver apartment a day after police said he opened fire and set off gas canisters in a suburban theater minutes into the premiere of the Batman film "The Dark Knight Rises." At least 70 people were wounded
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 U.S. 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 Holmes had recently withdrawn from a competitive graduate program in neuroscience; neighbors and former classmates in California have said he was a smart loner who said little.
But he had apparently prepared the attack at the Aurora theater 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.
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 neutralized 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.
Holmes, 24, was in solitary confinement for his protection at a county detention facility Saturday, held without bond on suspicion of multiple counts of first-degree murder. He was set for an initial hearing on Monday 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 were likely 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 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."