WASHINGTON - The FBI released this timeline of Navy Yard shooter Aaron Alexis' activity the morning of Monday, Sept. 16, 2013, the day of the mass shootings:
7:53 a.m.: Alexis' rental car, a blue Toyota Prius with New York plates, entered Parking Garage 28 at the Washington Navy Yard, located directly across from Building 197.
8:08 a.m.: Alexis exited Parking Garage 28 on foot carrying a backpack. Alexis entered Building 197 and proceeded to the elevator.
8:09 a.m.: Alexis exited the elevator on the 4th floor and entered the men's bathroom carrying a backpack and a clipboard.
8:15 a.m.: Alexis crossed the hallway into the 4 West area of Building 197 with shotgun, but without the backpack or a clipboard.
8:16 a.m.: Alexis shot the first victim in the 4 West area of Building 197.
8:17 a.m.: First 911 call is received from the 4th floor of Building 197.
8:20 a.m.: Alexis left the 4th floor using the stairs and entered the 3rd floor.
8:28 a.m.: Alexis appeared on the 1st floor.
8:57 a.m.: Alexis returned to the 3rd floor.
9:25 a.m.: Law enforcement shoot and kill Alexis on the 3rd floor.
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