Aaron Alexis used a legally purchased 12-gauge shotgun to kill 12 people at the Washington Navy Yard Monday morning and likely picked up a Glock handgun from one of his victims, according to the FBI.

FBI Assistant Director Valerie Parlave told reporters Alexis walked in to Building 197 with a Remington 870 shotgun. Alexis purchased the weapon at a Lorton, Va., gun shop, reports the Wall Street Journal.

Alexis didn't have an AR-15 rifle as several news outlets reported Monday. Two additional weapons were found on Alexis, including a Glock semi-automatic handgun, reports the Washington Times.


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