Two Aurora (Colo.) Police Department SWAT officers likely prevented further deaths at the Century 16 movie theater shooting Friday, when they quickly identified James Holmes as the suspect.

The officers spotted Holmes—dressed like a SWAT officer and clad in a ballistic helmet, body armor, a load-bearing vest, gas mask, and other tactical gear—behind the theater after the shooting and questioned him, Aurora Police Chief Dan Oates told CBS' Face the Nation.

The officers noticed Holmes was wearing non-police tactical gear and apprehended him after a shooting rampage that claimed the lives of 12 people at a screening of "The Dark Knight Rises."

Holmes had opened fire inside the theater with a Smith & Wesson M&P15 rifle, Remington 870 shotgun, and .40-caliber Glock. A second .40-caliber Glock was recovered from his vehicle.

A federal law enforcement official told the Washington Post that a weapon malfunction likely saved lives by forcing Holmes to abandon the M&P15 he had equipped with a 100-round drum magazine after it jammed.

In the two months leading up to the shooting, Holmes stockpiled ammunition mostly with online orders. He had purchased about 6,000 rounds of ammo, some of which he had delivered to his workplace at the University of Colorado's Anchutz Medical Campus, reports Bloomberg.

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