AURORA, Colo. - A controlled explosion by a bomb squad on Saturday appears to have made it safe for police to enter the booby-trapped apartment of the man suspected in Friday's mass shooting at a Denver-area movie theater, police said.
Police were undertaking the delicate task of disabling what they described as sophisticated explosives at the Aurora, Colorado, apartment of suspect James Holmes, who officials believe booby trapped his home before killing 12 people and injuring more than 50 others at the theater early on Friday.
The bomb squad used a robot to place a tube -- known as a "water shot" -- near an explosive device in the apartment. The water shot was then detonated to disable the explosive.
Photos of the apartment, taken by a camera raised up to the third-floor window, showed jars of ammunition on the floor and "things that look like mortar rounds," Aurora Police Chief Dan Oates said. There were also bottles filled with an unknown liquid as well as what appeared to be trip wires laid out across the apartment, he said.
Aurora Police spokeswoman Sergeant Cassidee Carlson said the device had clearly been "set up to kill."
"We have been successful in disabling a second triggering device," she said. "Although not certain, we are hopeful we have eliminated the remaining major threats. We will not know this until we enter the apartment."
"There still remains all kinds of hazards inside the apartment," Carlson said. "We will remain here for hours to collect evidence and mitigate those hazards."
Police evacuated five nearby buildings and created a perimeter of several blocks around Holmes' apartment, the top-floor unit of a three-story red brick building in a run-down section of Aurora.
The shooting occurred as hundreds of people watched sold-out midnight screenings of "The Dark Knight Rises" at a mall in Aurora.
The gunman -- armed with an assault rifle, a shotgun and a pistol, and wearing a full suit of tactical body armor, a helmet and a gas mask -- set off two smoke bombs before opening fire in the dark theater.
Officers who arrived on scene within 90 seconds of the first emergency calls quickly took Holmes, 24, into custody in a parking lot behind the cinema, where he surrendered without a fight, Oates said.
Holmes, a graduate student who authorities said had his hair dyed red and called himself "the Joker" in a reference to Batman's comic-book nemesis, was due to make an initial court appearance on Monday.
Hospital officials said some patients had sustained serious head injuries and chest injuries.
The University of Colorado Hospital, which treated 23 victims of the shooting, said 10 people had been released and five remained in critical condition.
The Medical Center of Aurora said of its seven patients -- ranging in age from 16 to 31 -- four remained in the intensive care unit and three other patients are on the main trauma floor.
"The initial adrenalin rush of having something like this happen, both for the families and the patients themselves, is starting to wear off," said Dr. Bob Snyder, a trauma surgeon at the Medical Center of Aurora. "There is going to be some realization that there are going to be some serious, long-term issues that people are going to have to deal with."
A memorial of flowers, candles and stuffed animals has been set up at the Aurora shopping mall where the shooting rampage took place. A handwritten sign read: "7/20 gone not forgotten."
President Barack Obama called the shootings a reminder that life is fragile and promised that the federal government stood ready to do all it could to seek justice for the "heinous crime.
"Even as we come to learn how this happened and who's responsible, we may never understand what leads anyone to terrorize their fellow human beings," Obama said in his weekly radio and Internet address, which was broadcast on Saturday.
Witnesses at the movie theater told of a horrific scene, with dazed victims bleeding from bullet wounds, spitting up blood and crying for help. Among those taken to hospitals as a precaution was a baby boy just a few months old.
"I slipped on some blood and landed on a lady. I shook her and said, 'We need to go; get up,' and there was no response, so I presumed she was dead," said Tanner Coon, 17.
The suspect may have blended in with other moviegoers who wore costumes as heroes and villains, and some witnesses said they believed at first that his appearance was a theatrical enhancement to the film.
"It was just straight chaos," said Jennifer Seeger, 25. "Everybody was starting to scream and run at that point. He went straight from here to here with a gun in my face at that point. That rifle was in my face and I honestly didn't know what to think."
The shooting evoked memories of the 1999 massacre at Columbine High School in Littleton, 17 miles from Aurora, where two students opened fire and killed 12 students and a teacher.
The gunman was armed with an AR-15 assault rifle, a 12-gauge shotgun and a Glock .40-caliber handgun, Oates said. Police found an additional Glock .40-caliber handgun in his car, parked just outside the theater's rear emergency exit, he said.
Holmes had purchased the weapons legally at three area gun stores in the last 60 days and bought 6,000 rounds of ammunition, including a 100-round drum magazine for an assault rifle, Oates said.
He said police had not yet determined whether the rifle was fully or semi-automatic. Still, with the 100-round drum in place, the shooter could easily have squeezed off 50 to 60 shots in a minute, Oates said.
A law enforcement official who asked to remain anonymous said the suspect had purchased a ticket, entered the theater and propped open the emergency exit while he slipped out to "gear up" and return armed.
The portrait of Holmes that emerged in the day following the shooting remained fuzzy, with only a speeding ticket on his record and nothing to suggest he was capable of an outburst of gun violence.
Holmes' family issued a statement of sympathy for the victims, saying, "Our heart goes out" to their loved ones, while they also asked for privacy from the media while they "process this information.