AURORA, CO. - Bomb experts detonated a second explosive device Saturday after disarming a trip wire attached to another bomb in the booby-trapped apartment of the suspected gunman who police say killed 12 and wounded 58 in a shooting rampage in a packed movie cineplex.
Police closed off several blocks around the building ahead of igniting the small bomb, yelling "fire in the hole!" three times before an explosion could be heard.
Aurora police Sgt. Cassidee Carlson had said investigators were closer to entering the apartment after authorities "defeated" the trip wire that was rigged to detonate when the front door was opened.
She said that "this is clearly set up to hurt somebody entering the apartment. It was set up to kill. This is serious stuff."
After disrupting the second device, authorities were deploying a robot to assess whether it was safe enough for bomb technicians to enter the apartment, a federal law enforcement official said.
The official, who is not authorized to comment publicly, said it was not clear when the unit could be determined safe for human entry.
"Everything is being dictated by level of safety," the official said. "There is no ticking clock."
The Associated Press, quoting a law enforcement official, reported that officers disarmed one explosive with a "water shot," a device that emits a shock wave and water. The official said the apartment appears to have three types of explosives: jars filled with accelerants, chemicals that would explode when mixed together and more than 30 "improvised grenades" that resemble commercially available aerial fireworks shells.
Earlier, Carlson told reporters that officials she called "the best of the best" had a plan that included first removing any trip wires, disposing of any incendiary devices and finally doing a controlled detonation that could result in a fire.
Carlson stressed the need to go slow for public safety but also to preserve any evidence that may be inside the apartment.
Fire department vehicles and ambulances were standing by. Chemists also are at the scene to identify chemicals. Power has been cut to the apartment buildings surrounding the area, forcing many people out into shady parking lots to escape the heat.
"It's safe right now with the evacuation. We don't need to rush anything" she said. "We don't want to lose evidentiary value. We're going to be very cautious with how we deal with things."
Aurora Police Chief Dan Oates halted the effort Friday, in part because his overworked force needed a break but also to bring in more bomb-disposal expertise. Oates called the booby traps "sophisticated and vexing."
Ammunition, bottles filled with liquids believed to be fire accelerants, gunpowder containers and 30 commercial-grade fireworks canisters known as mortars littered the apartment of the suspected shooter, James Holmes.
Authorities will alert people before anything happens and tell them what to expect. The controlled detonations could last all day.
The 30 shells commonly used in fireworks displays to be removed from the apartment will be put in a sand truck and taken to a disposal site where there will be a controlled detonation and evidence will be collected, Carlson said.
Carlson said there are still a lot of "unknowns" inside the apartment.
A federal law enforcement official said most of the incendiary material is arrayed in the living room of the approximately 800-square-foot apartment. The shells have been filled with smokeless powder that transform them into grenade-like devices, said the official, who was not authorized to comment publicly.
He said there also are containers of incendiary liquids that would work as accelerants. Ammunition also is scattered about to possibly explode in a fire.
Oates, after being informed of the danger by the first responding officers who looked into the unit's windows, later told colleagues in a planning meeting: "Thank God somebody saw that," the official said.
Aurora police called in federal bomb experts to break into the apartment, a small, one-bedroom in an aging, three-story building. Experts from the Bureau of Alcohol, Tobacco and Firearms were believed to be leading the bomb-removal effort.
As a precaution, Aurora police towed several vehicles this morning from the parking lot outside the building to reduce the danger of secondary fire and to give the bomb squad and firefighters more room to maneuver.
There was initial concern that the suspect may have planted explosives in the theater, either before or during the assault. That concern, the official said, slowed the removal of bodies from the theater.
Four other apartment buildings and several small businesses near the suspect's apartment building have been evacuated since Friday. Hundreds of residents were forced to move to an evacuation center at a nearby high school. Crime tape prevented residents and onlookers from an area of several blocks.
Police have not yet said when evacuees may be able to return home.
James Rodgers, who lives in a building just beyond the roped-off scene, said dozens of police officers and firefighters have surrounded the building since Friday morning.
"It's scary to think of what could go off in there," said Rodgers, 56. "I'm wondering why they didn't evacuate more of the area."
Friday evening, police escorted residents individually and in pairs to their apartment units so they could quickly gather personal items.
Roberto Martinez, who lives in a building next to the suspect's, had not been home since 4:30 a.m. Friday. He was escorted into his apartment and came out with a trash bag filled with items including toiletries, ice, a basketball and Air Jordan shoes.
He opted to stay in a hotel for the night instead of a shelter at a local high school, where some families with children were staying.
Joanne Southard, who manages a nearby apartment complex, said she has been impressed with the information coming from emergency managers. Investigators on Friday put a briefcase-sized air-quality monitor atop her building, The Fitz Apartments.
"It's kind of scary, but our emergency crews are handling it extremely well," she says. "They're keeping us very well informed."
Standing on the building's roof in the morning sun, Southard, 55, said she's confident it's far enough away to survive any explosion. But she said she is concerned whether there might be asbestos in the building.
"I think their biggest concern right now is if that building goes up and asbestos gets into the air," she said.