WASHINGTON (CBS/AP) The FBI released surveillance video of Navy Yard shooter Aaron Alexis and reiterated that he didn't appear to have targeted any specific individuals when he opened fire inside a building, killing 12 people.
Additionally, records recovered from Aaron Alexis's computer and cellphone reveal paranoia and mental health problems that authorities are investigating as the root cause.
Alexis, a 34-year-old former Navy reservist and IT contractor, used a valid badge to access the Navy Yard on the morning of Sept. 16 with a sawed-off Remington shotgun he had purchased two days earlier. He was killed by a U.S. Park Police officer following a rampage and shootout that police now say lasted for about an hour.
Authorities say Alexis had only recently started his job, and that although there was a "routine performance-related issue addressed to him" on the Friday before the shooting, there's no indication that he targeted particular co-workers or was motivated by problems in the workplace, said Valerie Parlave, head of the FBI's Washington field office.
"There is no indication that this caused any sort of reaction from him. We have not determined there to be any previous relationship between Alexis and any of the victims," Parlave said.
At the Pentagon on Wednesday, Deputy Secretary Ash Carter said the department will complete three separate reviews in late December, including internal and independent assessments of base safety procedures as well as the security clearance process.
"Bottom line is, we need to know how an employee was able to bring a weapon and ammunition onto a DoD installation, and how warning flags were either missed, ignored or not addressed in a timely manner," Carter said during a Pentagon briefing.
Carter said the reviews will include consideration of Navy Secretary Ray Mabus' recommendation that the department require that all police reports, not just arrests or convictions, involving an individual be included in background checks.
The Defense Department's internal review will be coordinated by the Pentagon's top intelligence official, Under Secretary Michael Vickers, and the independent review will be spearheaded by retired Navy Adm. Eric Olson and Paul Stockton, the former assistant secretary for homeland defense. A Navy review will be finished by the end of October; initial findings of the two larger reviews are due to the defense secretary by Nov. 15; and the final overall report will be done by Dec. 20.
The FBI's Parlave says Alexis held a delusional belief that he was being controlled by extremely low frequency waves, or ELF waves. Etched into the left side of the receiver of the shotgun he used in the attack were the phrases "Better off this way!" and "My ELF weapon!" Etched into the barrel of the shotgun were the words "End to the torment!" Etched into the right side of the shotgun receiver were the words "Not what yall say!"
The FBI released the following timeline, detailing Alexis' activity during the morning of September 16, 2013:
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 fourth 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 fourth floor of Building #197.
8:20 a.m. - Alexis left the fourth floor using the stairs and entered the third floor.
8:28 a.m. - Alexis appeared on the first floor.
8:57 a.m. - Alexis returned to the third floor.
9:25 a.m. - Law enforcement shoot and kill Alexis on the third floor.
The weapons recovered at the scene are being examined still, but the FBI did say the shotgun used at the scene had been modified with a sawed-off barrel, and had purple duct tape covering the end.
Alexis backpack was found to have included a roll of purple duct tape and "electronic media." The FBI said the media "revealed several relevant communications," although they did not elaborate, except to say the communications had indicated "that Alexis was prepared to die during the attack and that he accepted death as the inevitable consequence of his actions."
The FBI also said a document retrieved from his electronic media stated: "Ultra low frequency attack is what I've been subject to for the last 3 months, and to be perfectly honest that is what has driven me to this."
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