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FBI releases CCTV of Navy Yard gunman Aaron Alexis' attack FBI releases CCTV of Navy Yard gunman Aaron Alexis' attack
(35 minutes later)
The FBI has released chilling video footage of the Navy Yard gunman prowling the corridors of the complex as he hunts for victims. The FBI has released chilling video footage of the Washington DC Navy Yard gunman prowling the corridors of the complex as he hunts for victims.
During a press conference, the agency said that Aaron Alexis, 34, believed he was being controlled by extremely low frequency radio waves. During a press conference, the agency said that Aaron Alexis, 34, had believed he was being controlled by extremely low frequency radio waves.
He killed 12 people in the rampage on 16 September before he was shot by police in a gun battle. He killed 12 people in the rampage on 16 September before he was shot by police in a running gun battle.
Officials say they believe he did not target any specific individuals.Officials say they believe he did not target any specific individuals.
Clear video footage taken from the Navy Yard's gate and at locations on site shows Alexis calmly entering the complex.Clear video footage taken from the Navy Yard's gate and at locations on site shows Alexis calmly entering the complex.
'Conspiracy theories'
Later clips show him stalking a corridor armed with a shotgun and checking if a room is empty, before running down a flight of stairs.Later clips show him stalking a corridor armed with a shotgun and checking if a room is empty, before running down a flight of stairs.
Valerie Parlave, head of the FBI's field office in Washington, said in Wednesday's news conference they were still investigating Alexis' background and motivations. The agency also released images of the weapons Alexis used during the shooting. A photo of his backpack, which he used to hold the shotgun components and then left in a men's toilet in the building, was also published by the FBI.
But she noted that he had a well-documented history of mental health issues. He had written "my ELF weapon" - apparently referring to extremely low frequency waves - and "Better off this way!" on a Remington 870 shotgun.
He had written "my ELF weapon" - apparently referring to extremely low frequency waves - on the shotgun he used during the shooting. Valerie Parlave, head of the FBI's field office in Washington, said in Wednesday's news conference that they were still investigating Alexis' background and motivations.
But she noted the former Navy reservist had a well-documented history of mental health issues.
Ms Parlave said: "At this point I can confirm that there are multiple indicators that Alexis held a delusional belief that he was being controlled or influenced by extremely low frequency, or ELF, electromagnetic waves.
"The etching... is believed to reference theses electromagnetic waves.
"In addition, a document retrieved from the electronic media stated 'ELF attack is what I've been subject to for the last three months, and to be perfectly honestly that is what has driven me to this'."
Ms Parlave added: "ELF technology was a legitimate programme for naval subtonal submarine communications.
"However, conspiracy theories exist which misinterpret its application as the weaponisation of remote neural frequencies for government monitoring and manipulation of unsuspecting citizens."
As a IT subcontractor, Alexis had an entry pass to the Navy Yard complex.