Police Chief Dan Oates says 12 people are dead following a shooting during the "Dark Knight Rises" premiere at a movie theater in Aurora, Colorado, a suburb of Denver.
He says 50 others were injured when gunfire erupted around midnight Thurdsay at the Aurora theater.
Oates says one gunman stood at the front of the Century 16 Theaters at the Aurora Mall. He says witnesses told officials he released some sort of canister. They heard a hissing sound and some gas emerged and then the gunman opened fire.
Several sources have now confirmed the suspect's identity as 24-year-old James Holmes. Holmes is a white male born in December of 1987. He was in possession of three guns when police arrested him in the parking lot of the theater.
Our NBC affiliate, KUSA-TV in Denver, is also reporting that Holmes told police his apartment is booby trapped with explosive devices. Police have evacuated five buildings in the surrounding area as a precaution. The bomb squad is examining the apartment which is located on the corner of East 17th Avenue and Peoria Street in Aurora.
"I saw at least four people limping, slightly bloody, the most I saw was a girl covered in blood with no wounds, it kind of made me think the worst," said one witness. "A cop came walking through the front door before it was under control holding a little girl in his arms and she wasn't moving."
There was no immediate word of any motive.
Police say one person has been arrested and there is no evidence of any additional shooters.
Witness Hayden Miller told KUSA that he was inside Theater 16 and heard several shots.
"Like little explosions going on and shortly after that we heard people screaming," Miller said to KUSA.
Hayden also said at first he thought the sounds were coming from a movie in the adjacent theater. But then he saw "people hunched over leaving theater."
Two other victims are reported to be in critical condition and rushed to nearby Swedish Medical Center according to spokeswoman Nicole Williams.
Williams also said emergency crews are at the ready and they are expecting several more patients from the scene.
"We're on standby to receive," she said.
Aurora is located in southeast suburban Denver, about 10 miles from downtown.
Police Chief Dan Oates has Michigan ties, he was the police chief in Ann Arbor from 2001 through 2005.