Ventura County Sheriff Geoff Dean has identified Southern California bar gunman as 28-year-old Ian David Long. There is no known motive for the shooting, the sheriff said, adding that the suspect shot at random inside the bar.
Dean explained that police officers immediately engaged Long on the scene and he likely killed himself.
According to a neighbor, who knew the gunman, Long suffered from Posttraumatic stress disorder (PTSD).
"I don't know what he was doing with a gun," the woman said.
Sgt. Ron Helus with the Ventura County Sheriff's Department was among the 12 killed and will be honored at 10 a.m. with a procession, Dean proceeded to say.
READ MORE: WATCH First Responders at Crime Scene After Dramatic California Bar Shooting
When the gunfire started on Wednesday night at Borderline Bar & Grill in Thousand Oaks, a distant suburb of Los Angeles, people who were dancing dropped to the floor and hid behind chairs and counters in stunned silence, according to media reports.