Aaron Alexis Carved Messages Into Shotgun: "Better Off This Way" and "My ELF"

Complained to police about being targeted by microwaves and followed by unknown officials

The shooter who killed 12 people at the Washington Navy Yard on Monday carved two cryptic messages into the wooden stock of his shotgun – "(Better Off This Way)" and "(My ELF)" -- according to a federal law enforcement official.

The messages appear to be the first clue into Aaron Alexis' possible motive for attacking the base at the start of the work week after spending weeks drifting up and down the East Coast and complaining of hearing voices and believing he was being stalked by three unknown officials.