Colorado police have disabled a tripwire at the booby-trapped apartment of the suspect accused of the Denver Batman shootings.

Aurora police spokeswoman Sergeant Cassidee Carlson said: "We have been successful in defeating the first threat, which includes defeating the tripwire and the first incendiary device.

"What you need to understand is that this tripwire was set up to clearly detonate when somebody entered that apartment and it was set up to kill that person."

"In the second phase, this may include the controlled detonation of another triggering mechanism.

"If that's to occur, keeping public safety in mind, we'll be shutting down Peoria Street behind me and doing a reverse 911 call and you all will be notified. Shall this controlled detonation occur, there will be a loud boom associated with that," she said.

The shooting occurred in the early hours of Friday morning as hundreds of people watched a midnight screening of The Dark Knight Rises at a mall in Aurora.