According to authorities, a delusional Aaron Alexis claims that he was controlled by a series of low frequency electromagnetic waves in the last few months. It was this that supposedly drove him to shoot at a group of employees at the Navy yard last week.

The FBI also released copies of a surveillance video that showed the shooter armed with a shotgun, patrolling the building stairwell of the naval complex where he committed the shootings. His ended up killing 12 people, and wounding 4 others.

There were many questions regarding the massacre, prompting Assistant Director of the FBI, Valerie Parlave, to refer to communication that her team had recovered from the shooter's laptop and other devices. The communication indicates that the shooter seemed to think that he was the target of some "low-frequency waves".

Alexis wrote that it was the low-frequency waves that had driven him to do what he did. Based on the sketched etchings and messages that were recovered from him, it seems as if Alex did have an obsession with the electromagnetic waves. There were references to ELF, which the FBI director has identified as extremely low frequency waves.

She went on to say that while ELF was a legitimate program used in sub-tonal marine communications, there have been conspiracy theories about it, suggesting that the government uses it to monitor people. The evidence seems to suggest that Alexis believed the conspiracy theories, which led him to act.

A month before the incident, police were called into Alexis' hotel room because he was distressed upon hearing voices coming from the roof and floor of his room.

Despite the unusual set of evidence gathered, none of it seemed to suggest that Alexis was targeting a specific individual.

Alexis was killed by the police in the attempt to stop him.