A video footage of Washington DC Navy Yard gunman Aaron Alexis prowling the corridors of the complex as he hunts for victims has been released by the FBI.
During a press conference, an FBI spokeswoman said Aaron Alexis, 34, believed he was being controlled by extremely low frequency radio waves.
Aaron Alexis killed 12 people in the rampage on September 16 before he was shot by police in a running gun battle.
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 Aaron Alexis calmly entering the complex.
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.
The agency also released images of a weapon Aaron Alexis used during the shooting.
He had written “my ELF weapon” – apparently referring to extremely low frequency waves – and “Better off this way!” on a Remington 870 shotgun.
Washington DC Navy Yard gunman Aaron Alexis prowling the corridors of the complex as he hunts for victims
A photo of his backpack, which he used to bring the weapon into the building and then left in a men’s toilet, was also published by the FBI.
Valerie Parlave, head of the FBI’s field office in Washington, said in Wednesday’s news conference that they were still investigating Aaron Alexis’ background and motivations.
But she noted the former Navy reservist had a well-documented history of mental health issues.
Valerie 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 these 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 honest that is what has driven me to this>>.”
Valerie 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 an IT subcontractor, Aaron Alexis had an entry pass to the Navy Yard complex.
Investigators say he acted alone and died on the third floor of Naval Sea Systems Command headquarters after about an hour of exchanging gunfire with officials.
The shooting has led to questions about how Aaron Alexis received the security clearance necessary to be a contractor and enter the installation and prompted calls to review the government vetting process.
Also on Wednesday, Washington Police Chief Cathy Lanier told local media a Washington DC police officer was shot in the chest while responding the shootings but was saved by protective gear.
Another police officer was shot in the leg and is currently recovering in hospital.
A government audit has found that budget cuts may have been the cause for lax security at the Washington D.C. Navy Yards where 12 people were shot dead and eight others were injured on Monday morning.
According to a yet-to-be-released government audit, federal oversight investigators concluded that the reduced security measures at the base left security risks unaddressed.
A report by the Department of Defense Inspector General’s office shows that they were concerned about the access that would be granted to outside contractors – like that of Aaron Alexis, the suspect who was killed by police during the Monday morning shooting.
The report states that the Navy “did not effectively mitigate access control risks associated with contractor installation access” to the Navy Yards.
Time Magazine published excerpts from the report after having been read portions by an unidentified federal official who had access to the Inspector General’s findings.
The security risks are placed squarely on the Navy administrators who were trying “to reduce access control costs”.
The process of gaining access to the administrative facility- where about 3,000 people work- is under severe scrutiny.
In a Monday night press conference, FBI assistant D.C. director in charge Valerie Parlave said that they concluded Aaron Alexis had legitimately accessed the building as his status as a contractor would have given him sufficient credentials to enter unquestioned.
Budget cuts may have been the cause for lax security at the Washington D.C. Navy Yards where 12 people were shot dead and eight others were injured
“He utilized a valid pass,” Valerie Parlave said during the press conference.
Aaron Alexis, 34, became a full-time Navy reservist in 2007 but was dismissed in 2011 following a series of ‘misconduct’ violations.
As a contractor for a group working for a subcontractor used by Hewlett-Packard, Aaron Alexis had the proper identification to be allowed into Navy Yard’s Building 179 where he began shooting.
“He did have a secret clearance. And he did have a CAC [common access card],” said Thomas Hoshko, CEO of subcontracting group The Experts Inc who employed Aaron Alexis.
Asked when Aaron Alexis was supposed to start work, Thomas Hoshko told Reuters that it was unclear when Alexis was supposed to start his latest stint in the government facility: “That’s what I got to find out, if he was supposed to start today … It’s not clear to me.”
“We had just recently re-hired him. Another background investigation was re-run and cleared through the defense security service in July 2013.”
Another problem with Aaron Alexis that should have been flagged up by the security access system is that he had two prior arrests- one in 2004 for shooting someone’s tires in an anger-fueled “blackout” and another in 2010 when he said that he accidentally fired into a neighbor’s apartment while cleaning his gun.
The security assessment report cites the fact that a number of people with criminal histories were able to bypass the Navy Yard’s security without any alarm.
Time reports that the audit cited 52 instances where “convicted felons received routine unauthorized installation access, placing military personnel, attendants, civilians in installations at an increased security risk”.
The research into the security inefficiencies at Navy Yard began in September 2012 and carried on through August of this year. The final report will be published within the next 30 days.