A police chief says a Colorado shooting suspect's apartment is posing a "vexing problem" as officers face challenges in safely entering the residence where booby traps were set.
Colorado 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.
Holmes is 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.
Aurora Police Chief Dan Oates said photos of Holmes' apartment appeared to show trip wires, jars full of ammunition and liquid and other items unlike anything the chief has ever seen.
Police on Friday evening escorted residents seeking to gather personal items into several apartment buildings in the area that were evacuated.