Video - National News
Posted on July 20, 2012 at 4:01 AM
Updated Friday, Jul 20 at 10:00 PM
A former medical student in a gas mask barged into a crowded Denver-area theater during a midnight showing of the Batman movie on Friday, hurled a gas canister and then opened fire, killing 12 people.
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Credit: Katrina Gutierrez / WFAA