Shooting Suspect Trapped Apartment Police are trying to enter the Colorado shooting suspect's apartment but have been forced to move cautiously after spotting booby traps with trip wires. Firefighters are monitoring the Aurora apartment building for gases in an effort to determine what chemicals they say 24-year-old James Holmes might have used to trap the place - in case the materials go off, authorities said. Police evacuated the building and surrounding residences after arresting Holmes as the suspect in a mass shooting Friday at a midnight screening of "The Dark Knight Rises." Twelve people were killed in the attack and dozens were injured, including 11 victims who remained in critical condition, authorities said. FBI agents and police discovered it was booby-trapped when they used a camera at the end of a 12-foot pole to look inside. There are three containers and we don't know what's inside," said Chris Henderson, deputy Aurora fire chief. Police Chief Dan Oates said officers will try to gain entry on Saturday. Photos of Holmes' apartment appeared to also show jars full of ammunition and liquid and other items unlike anything the chief had ever seen. "I personally have never seen anything like what the pictures show us is in there," Oates said. Police use a video camera to look inside an apartment where the suspect in a shooting at a movie theatre lived in Aurora, Colo., Friday, July 20, 2012. As many as 12 people were killed and 50 injured at a shooting at the Century 16 movie theatre early Friday during the showing of the latest Batman movie. Friday evening police escorted residents in ones and two to their apartment units so they could quickly gather personal items. Roberto Martinez, who lives in a building next door to the suspect's building, hadn't 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 some Air Jordans. 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. More than two dozen people were using a shelter at the Aurora Central High School Gymnasium. Red Cross spokeswoman Melinda Epp said up to 30 residents were using the shelter to escape the heat, feed their children and wait out their exile. It was unclear how many people planned to spend the night there. Kaitlyn Fonzi, 20, a graduate student at University Hospital, said she lives in the apartment below that of the suspect. About midnight, Fonzi said she heard techno-like, deep-based reverberating music coming from that unit apartment. She went upstairs to the suspect's place and put her hand on the door handle. She felt it was unlocked, but she didn't know if he was there and decided not to confront him. "I yelled out and told him I was going to call the cops and went back to my apartment," she said. Fonzi called police, who told her they were busy with a shooting and did not have time to respond to a noise disturbance. She said she was surprised to learn later that the apartment was booby trapped and was shaken by the news. "I'm concerned if I had opened the door, I would have set it off," she said. Fonzi said she had seen the man one or two times before but never talked with him. She said she believes the music was on a timer because it started about the time of the shootings. Police have searched apartments and broken out windows at the building, but Fonzi said she doesn't know the condition of her apartment or car.