Cinema Killer's Home Rigged To Explode

The death penalty trial of Colorado cinema gunman James Holmes has entered its sixth day, with a lead detective in the case describing the killer's booby-trapped apartment.

Aurora police Detective Craig Appel testified Holmes told investigators he had rigged his apartment with several devices set to explode.

Holmes built a "trip wire" using fishing line that would trigger the devices when someone entered through the front door, Detective Appel said.

He also created a recording with loud music in the hope that a neighbour would call police to come and investigate.

Special Agent Garrett Gumbinner, a bomb technician with the FBI, told jurors that his team had to break through a side window to gain access to the apartment.

The court was shown photographs taken from a bomb robot's camera that revealed a maze of objects inside Holmes' residence.

Mr Gumbinner said authorities were "gravely concerned" when they noticed the fishing line running from the door to a thermos that was sitting on a frying pan.

Holmes told investigators the items contained "glycerine and otassium permanganate", which would set off sparks and fires if mixed, Mr Gumbinner said.

Soda bottles containing petrol and two jars of napalm were also placed at points around the apartment.

Asked by the prosecution what would have happened had someone triggered the trip wire, Mr Gumbinner said: "It would have made the whole apartment explode, killing or maiming whoever was there at the time."

Holmes used air fresheners throughout the residence to help mask the smell of the petrol, the agent said.

Jurors also heard testimony on Tuesday from the director of the University of Colorado neuroscience programme, where Holmes was enrolled as a graduate student.

Sukumar Vijayaraghavan was on the programme's admissions committee when Holmes applied in 2011, and later served as Holmes' mentor.

He testified that he was impressed with Holmes' understanding of research and rated him "quite highly" during the application process.

He described Holmes as being "quiet and a little socially awkward, but definitely someone who had the calibre to be in the programme".

As Holmes progressed through his first year, however, some of his lab professors expressed concern that he was not engaged and had difficulty communicating with fellow students, Mr Vijayaraghavan told the court.

He said one professor was concerned that Holmes' presence in the lab would impact moral.

Mr Vijayaraghavan said he met with Holmes in June 2012 to discuss his performance, at which time Holmes informed him he was quitting the programme.

"That was unexpected," he told the court.

On Monday, jurors got their first glimpse of a video that showed Holmes talking to detectives after the 2012 shooting rampage that left 12 people dead and 70 injured.

In the video, Holmes asked: "There weren't any children hurt, were there?"

Detectives did not answer the question directly, responding: "We'll get to that."

The youngest victim of the 20 July 2012 shooting was six-year-old Veronica Moser-Sullivan. The other 11 victims ranged in age from 18 to 51.

Last week, prosecutors called on several survivors who provided emotional descriptions of the shooting that occurred during a midnight screening of the Batman film The Dark Knight Rises.

Holmes, 27, has pleaded not guilty by reason of insanity.