James Holmes was a patient of a University of Colorado psychiatrist before the attack in Aurora, Colorado, which killed 12 people and wounded scores more, according to a court document filed Friday by his lawyers.

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The killings of 26 people there followed a July rampage in a movie theater in Aurora, Colorado, that left 12 dead and the August attack on a Sikh temple in Wisconsin that killed another six.

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The attack, which took place at the premiere of the new Batman film in Aurora, was one of the worst mass shootings in US history.

BBC: Batman suspect James Holmes 'set booby-traps' in flat

The attack, which took place at the premiere of the new Batman film in Aurora in July, was one of the worst mass shootings in US history.

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