Aurora, Colorado Shooting - Update 4

Here is the latest press conference:

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And here from MSNBC.com is the latest article expanding on that update: By Miranda Leitsinger and Miguel Llanos, NBC News AURORA, Colo. -- The booby-trapped apartment of mass shooting suspect James Eagan Holmes was "designed to kill," officials said Saturday as they described a complex operation to disarm sophisticated explosives without destroying evidence. "This was certainly challenging," said FBI agent Jim Yacone, detailingthe discovery of the explosive devices and the use of a robot to disarm a trip wire and a primary bomb. "The threat has not been completely eliminated," Yacone said, while adding that enough progress had been made that "an extensive amount of evidence is in the process of being collected." Aurora Police Chief Dan Oates told reporters that he believed the rigged apartment targeted the police. “We sure as hell are angry,” he said. "This apartment was designed to kill whoever entered it," he said. "Make no mistake about it." Holmes had received a "high volume of deliveries" over the last four months at home and at work, which would explain how he obtained thousands of rounds of ammunition, Oates said. He said it could take another day to fully dismantle explosives in the apartment and collect evidence, adding that residents of four neighboring buildings could be allowed to return Saturday night. Residents of the building where Holmes lived might be allowed back on Sunday, he said. Specialists earlier Saturday set off a small, controlled detonation inside the apartment after first disarming a trip wire and incendiary device.

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Aurora Police Chief Dan Oates told reporters that he believed the rigged apartment targeted the police. “We sure as hell are angry,” he said. "This apartment was designed to kill whoever entered it," he said. "Make no mistake about it." Holmes had received a "high volume of deliveries" over the last four months at home and at work, which would explain how he obtained thousands of rounds of ammunition, Oates said. The blast succeeded in disarming a second triggering device, Aurora Police Sgt. Cassidee Carlson told reporters. A siren and shouts of "Fire in the hole" preceded the blast. Live video showed the blast blowing out part of a window, but no smoke or fire resulted. "The controlled detonation was successful," the Aurora Police Department said in a statement. "Still more work to be done in the apartment to include dealing with other devices. There is a possibility of more controlled detonations." The 800-square-foot apartment appears to have three types of explosives, a law enforcement source told the Associated Press: jars with accelerants; chemicals that would explode when mixed together; and more than 30 "improvised grenades" that resemble commercially available aerial fireworks shells . Before the detonation, Carlson announced a trip wire and explosive had been disarmed, saying "we have been successful in defeating the first threat." She added that "another triggering mechanism" had been found inside, and that was later followed up with the controlled detonation. "We're going to be very cautious," she added, because "we don't want to lose" any evidence. Any undetonated explosives will be taken in trucks lined with sand to take the impact of any explosion, she said, adding that some 30 aerial shells are among the items detected inside the apartment on Friday. Fire trucks surrounded the building on Saturday as a precaution. Some adults and children in nearby buildings not evacuated watched from balconies. Earlier Saturday, streets around the building were cleared, four neighboring buildings were evacuated and some unattended vehicles were towed away. On Friday, tenants in Holmes' apartment building cleared out, taking with them a few belongings. The Red Cross said Saturday that 16 evacuees were in one of the agency's shelters. The building is in a lower-income area about four miles from where the shootings took place during a midnight premiere of the Batman movie "The Dark Knight Rises". He said it could take another day to fully dismantle explosives in the apartment and collect evidence, adding that residents of four neighboring buildings could be allowed to return Saturday night. Residents of the building where Holmes lived might be allowed back on Sunday, he said. Specialists earlier Saturday set off a small, controlled detonation inside the apartment after first disarming a trip wire and incendiary device.