By Keith Coffman and Stephanie Simon
AURORA, Colo. (Reuters) - A masked gunman killed 12 people at a midnight premiere of the new Batman movie in a suburb of Denver early on Friday, sparking pandemonium when he hurled a gas canister into the auditorium and opened fire on moviegoers.
About 50 others including children were hurt in the attack on the showing of "The Dark Knight Rises" in a mall in the Aurora suburb, some of whom were treated for the effects of tear gas, hospital officials said.
"This is one of the most horrific nights I've ever had to work," said Comilla Sasson, an emergency doctor at University of Colorado Hospital in Aurora where 22 patients ranging in age from three months to 45 years arrived in private cars, police cars and ambulances.
Police took the suspect into custody in the parking lot behind the theater, Aurora Police Chief Dan Oates told a news conference.
Multiple media outlets named the suspect as James Eagan Holmes, 24, though Reuters could not independently confirm his identity.
The gunman appeared at the front of the theater during the movie and released a canister which let out a hissing sound before gunfire erupted, police said.
Dozens of police were at the scene, and the authorities evacuated the area while they checked for any explosive devices. They said there was no evidence of a second gunman.
Police also searched the suspect's apartment building, breaking into a second-floor window after officers had been lifted in a crane, looking for explosives after the suspect made statements about explosives in his home. Police and sheriff's deputies from several jurisdictions swarmed the scene with heavy weaponry trucks from the bomb squad.
"When we got out of the theater it was just chaos. There was this one who guy was on all fours crawling. There was this girl spitting up blood," witness Donovan Tate told KCNC television. "There were bullet holes in some people's backs, some people's arms. There was this one guy who was stripped down to just his boxers. It looked like he was shot in the back or something. It was crazy."
Confusion reigned as shooting broke out during an action scene in the summer blockbuster, one of more highly anticipated films of the year. He may have blended in with other movie-goers who wore costumes as heroes and villains.
"He looked like he was in the military or like he was a SWAT person so he just kind of blended in with the chaos of the crowd. People thought he was probably like a cop or something," witness Jennifer Seeger told NBC's "Today."
"He came in and threw in the gas can and then I knew it was real. He shot the ceiling and right after he shot the ceiling he pointed the gun right at me. At that point I dove into the aisle. And I got lucky because he didn't shoot me," she said.
President Barack Obama, who was notified of the shooting early on Friday morning by his homeland security adviser, John Brennan, urged Americans to "stand together" with the people of Aurora in the hours and days to come.
"Michelle and I are shocked and saddened by the horrific and tragic shooting in Colorado. Federal and local law enforcement are still responding, and my administration will do everything that we can to support the people of Aurora in this extraordinarily difficult time," Obama said in a statement.
"As we do when confronted by moments of darkness and challenge, we must now come together as one American family," he added.
MEMORIES OF COLUMBINE
Colorado has suffered mass killings in the past. In 1999, two students opened fire at Columbine High School in the suburb of Littleton, also near Denver, killing 12 students and a teacher.
Aurora Police spokesman Frank Fania said the suspect was carrying a knife, a rifle and a handgun when arrested, and one other gun was recovered from the theater. The gunman was also wearing a bulletproof vest.
"He did not resist, he did not put up a fight," Fania said.
Chandler Brannon, 25, who had been watching the movie with his girlfriend, said that about 20 minutes into the movie he saw a smoke bomb go off and heard what sounded like fireworks. He later realized they were a rapid volley of gunshots.
"I told my girlfriend to just play dead," he told Reuters, adding that he never got a full view of the gunman. "All I could see was a silhouette."
One man told an NBC affiliate he was in the adjacent theater watching another screening of the Batman movie when he heard gunshots and the theater filled with thick, choking smoke.
He saw bullets holes in the wall, and some people in his theater were wounded. "I heard moaning ... they were in pain."
Fania said police received the first call about the shooting at 12:39 a.m. local time (06:39 GMT) and responded within "a minute or two."
Local hospitals were alerted to a "mass casualty incident." Fania told NBC News that 10 of the victims died in the theater and two died in the hospital.
In New York, police will deploy officers at screenings of "The Dark Knight Rises" throughout the city "as a precaution against copycats," Police Commissioner Raymond Kelly said in a statement.
Time Warner-owned Warner Bros., the studio behind the film, canceled its premiere in Paris.
"Warner Bros. is deeply saddened to learn about this shocking incident. We extend our sincere sympathies to the families and loved ones of the victims at this tragic time," spokeswoman Jessica Zacholl said.
The film, with a budget of $250 million, opened on 4,404 screens, the second widest release ever behind "Twilight: Eclipse," and industry analysts had said it stood a good chance of matching or beating the opening weekend box office record of $207 million set by Disney's "Avengers" in May.
The prior release in the Batman series, "The Dark Knight," has grossed more than $1 billion at the worldwide box office since its release in 2008.
(Additional reporting by Stephanie Simon and Cynthia Johnston; Editing by Daniel Trotta and Vicki Allen)
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