
RJ Sangosti,/The Denver Post via AP
In this July 23, 2012 file photo, movie theater massacre defendant James Holmes sits during a pre-trial hearing in Arapahoe County District Court in Centennial, Colo.
Holmes had spent months planning the July 20, 2012 attack at an Aurora, Colorado movie theater that left 12 dead and 70 injured.
He had several high-powered weapons and fired "many, many rounds," according to Police Chief Dan Oates.
Though he had worn body armor during the attack, "He surrendered without any significant incident," Oates said.
Holmes told the police he was "the Joker," the terroristic villain of the Batman franchise. He warned police that his apartment had been booby trapped. At the time Oates described what they found as an "incendiary device," but until now the public hasn't had a full picture of what extremes Holmes went to.
Now that the trial has concluded, and Holmes has been sentenced to life in prison without the possibility of parole, hundreds of photos of the jerry-rigged apartment have been released because of an open records request. Some of these images were used in the trial against him; all of them are shocking and disturbing.
Initially a robot was sent into the apartment to investigate and spray water on the explosives.

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Still images from an Aurora Police robot that entered the apartment of James Holmes.
Wires were strewn about the apartment linking different explosives. Oates told the Denver Post the devices were "pretty sophisticated," adding that "we could be here for days."

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Wiring found throughout the apartment of James Holmes.
A mixture of bullets, gunpowder, and a flammable liquid are wired to explode in Holmes' apartment.

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A glass container filled with bullets, gunpowder, and wiring found inside the apartment of James Holmes.
Among the improvised devices were 30 homemade grenades, pictured below.

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One of the devices found in the apartment of James Holmes.
Holmes' living room was littered with lighter fluid, containers of gasoline, and gunpowder.

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Explosives found in the apartment of James Holmes.

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Explosives found in the apartment of James Holmes.
These images are jarring. However, Army veteran Gary Smith, an explosives expert with the Bureau of Alcohol Tobacco Firearms and Explosives, whose team worked to diffuse the many bombs, told NBC that, "I really wasn't too scared."

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One of the devices in James Holmes' apartment.
During the investigation, an unnamed official told CNN that if the devices went off "you would have an explosion that would knock down the wall of (nearby) apartments." He added, "That flame would have consumed the entire third floor."

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An image from inside James Holmes' apartment.
Authorities say that there were 10 gallons of gasoline in different containers throughout the apartment.

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Soda bottles filled with gasoline inside James Holmes apartment.

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The scene inside the booby-trapped home of James Holmes.

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White gunpowder is seen on the carpet inside James Holmes apartment.
Besides the bombs, the apartment was relatively empty with little furniture. The Batman mask below is one of Holmes' few personal effects left behind.

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