UK & World News
Navy Gunman 'Believed He Was Being Controlled'
Washington Navy Yard gunman Aaron Alexis believed he was being controlled by extremely low-frequency waves, the FBI has said.
Valerie Parlave, the head of the FBI's field office in Washington, said the evidence showed Alexis acted alone during the September 16 shooting rampage that killed 12 people.
She said investigators were continuing to explore the background and motivations of the 34-year-old, but added Alexis had a well-documented history of mental health issues.
Ms Parlave said Alexis held a delusional belief that he was being controlled by extremely low-frequency, or ELF, waves.
Records recovered from Alexis' computer and mobile phone reveal paranoia and mental health problems that authorities are investigating as the root cause.
"We have found relevant communications on his electronic media which referenced the delusional belief that he was being controlled or influenced by extremely low-frequency electromagnetic waves for the past three months," Ms Parlave said.
A document recovered by agents from Alexis after the shooting read: "Ultra low-frequency attack is what I've been subjected to for the last three months, and to be perfectly honest that is what has driven me to this."
The FBI released surveillance video and images that show Alexis arriving at the Navy Yard and launching his attack on a mix of military and civilian personnel.
Images of the shotgun used in the attack showed Alexis had etched messages on the weapon, including "my ELF weapon" and "End the torment".
The former US Navy reservist and IT contractor was killed in a shoot-out with police after exchanging gunfire for an hour, Ms Parlave said.
She said Alexis had not targeted any specific individuals inside the building.
The shooting spree and the question of how Alexis got security clearance to enter the base have prompted calls for a review of the government vetting of private contractors.
At the Pentagon, Deputy Secretary Ash Carter said the department would complete three separate reviews in late December, including internal and independent assessments of base safety procedures as well as the security clearance process.
He said: "Bottom line is, we need to know how an employee was able to bring a weapon and ammunition onto a DoD (Department of Defense) installation, and how warning flags were either missed, ignored or not addressed in a timely manner."