Gunman who killed 12 died from self-inflicted gunshot

An autopsy has found the gunman who killed 12 at a Southern California bar died from a self-inflicted gunshot.

Police say Ian David Long, a 28-year-old ex-Marine machine-gunner, shot and killed 11 people at the Borderline Bar and Grill along with a police officer who responded just before midnight Wednesday.

Police said the officer exchanged gunfire with Long, who was found dead at the scene.

Ventura County Sheriff Bill Ayub said Saturday that an autopsy showed Long fatally shot himself.

Investigators say that based on time stamps, Long posted to Instagram during the attack.

The post involved his mental state and whether people would believe here was sane.

Authorities have yet to determine a motive.