2012 Aurora

On July 20, 2012, a mass shooting occurred inside a Century 16 movie theater in Aurora, Colorado, during a midnight screening of the film The Dark Knight Rises. Dressed in tactical clothing, James Eagan Holmes set off tear gas grenades and shot into the audience with multiple firearms. Twelve people were killed and seventy others were injured, 58 of them from gunfire. It was the deadliest shooting in Colorado since the Columbine High School massacre in 1999, and at the time had the largest number of casualties in one shooting in modern U.S. history, until the Orlando nightclub shooting in 2016 . Holmes was arrested in his car outside the cinema minutes later. Earlier, he had rigged his apartment with homemade explosives and incendiary devices, which were defused by the Arapahoe County Sheriff's Office Bomb Squad a day after the shooting.

The shooting prompted an increase in security at movie theaters across the U.S. that were screening the same film, in fear of copycat crimes. It led to a spike in gun sales in Colorado and political debates about gun control in the United States.

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