Holmes planned for a major explosion and fire

A judge in Aurora, Colorado heard frightening details from a FBI bomb technician about the booby trap system discovered at James Holmes's apartment. Holmes is charged with killing and wounding dozens inside a theater six months ago.

The technician said the apartment was set for three separate fires. Police believe Holmes left loud music playing to lure someone to the apartment. The fires would have been triggered once someone broke a trip wire at the door. It would have caused a massive explosion.

This is the second day of a preliminary hearing to determine if Holmes will stand trial. Later this week, his attorneys will be allowed to put on witnesses testifying as to his mental health. No word yet, as to whether Holmes defense will be an insanity defense.