Terror In DC: What We Know About Navy Yard Gunman Aaron Alexis [PHOTOS]
The shotgun Alexis used was purchased in a Lorton, Va. Gun shop and allegedly obtained a handgun and AR-15 assault rifle (pictured) during his initial attack according to the FBI. Although Alexis had a high-level security clearance, and he was allowed to enter the highly-guarded Navy Yard with proper identification. It was initially reported Alexis may have snuck his way in using someone else's ID.