On September 16 , 2013 , Aaron Alexis fatally shot twelve people and injured three others in the Washington Navy Yard using a shotgun on which he had written " my ELF weapon " , before being killed by responding police officers . The FBI federal law enforcement agency concluded that Alexis suffered from " delusional beliefs " that he was being " controlled or influenced by extremely low frequency electromagnetic waves "
fatally shot twelve people and injured three others
Washington Navy Yard shooting
Electronic harassment