New footage has been released showing a bomb squad robot entering the booby-trapped apartment of James Holmes, the mass-shooting gunman who killed 12 people in a Colorado movie theater in 2012.

Video footage showing one of the bomb squad's remote-controlled robots slowly entering his home and discovering up to 20 different bombs and incendiary devices, all rigged to blow, has been released, according to ABC News.

The raid took place July 21, 2012, just hours after the shooting occurred, prompting authorities to evacuate several of the buildings in the surrounding area.

In the video, multiple improvised explosives can be seen, including 16 black balls laying on the living room floor connected to a series of wires, as well as bottles filled with napalm and gasoline to add to the potential destruction, according to WDAM.

"His intent was to have law enforcement respond to a noise complaint at the apartment and trip the trip wire and set off the devices," said Gary Smith, an explosives enforcement officer who helped disarm the bombs back in 2012.

Holmes told authorities he had set a tape to play 40 minutes of silence before loud music was to play, prompting a response that would cause someone to trip one of the many deadly wires inside.

A neighbor testified in court that she responded to sounds coming from the apartment, but called the police instead of entering, according to Hawaii News Now.