What we know about the gunman in the Thousand Oaks bar shooting

Ian David Long, 28, is believed to have been the gunman in Wednesday night’s shooting at the Borderline Bar & Grill in Thousand Oaks, California, Ventura County Sheriff Geoff Dean said.

Authorities found the gunman dead inside an office adjacent to the bar’s entryway, Dean said. “We believe he shot himself.”

The gunman used a Glock 21 .45-caliber handgun designed to hold 10 rounds plus one in the chamber, but the gun had an extended magazine, the sheriff said. Investigators didn’t immediately know how many rounds the magazine could hold, he said.

Long was a US Marine Corps veteran, Dean said.

“We have no idea what the motive was at this point.”

Deputies are at Long’s home, seeking to serve a search warrant, Dean said.

Investigators believe Long arrived Wednesday night at the bar in a car, shot a security guard who was standing outside and then stepped inside. It appears that Long then shot other security workers and employees inside and opened fire further inside the club, Dean said.

Law enforcement had several previous contacts with Long, including in April, when officers were called to a disturbance at his home, the sheriff said.

“He was somewhat irate, acting a little irrationally,” Dean said. Mental health specialists talked to him and didn’t feel he qualified to be detained under the state’s “5150” mental health detention law, Dean said.

Long also had been a victim of battery at a different Thousand Oaks bar in January 2015, the sheriff said.

Full coverage: Deadly Thousand Oaks bar shooting 

The shooter started firing suddenly

The gunman was dressed in a black trench coat and wearing glasses when he walked into the bar filled with people enjoying a night of line dancing.

“I started hearing these big pops. Pop, pop, pop. There was probably three or four, I hit the ground,” John Hedge told CNN affiliate KABC.

Holden Harrah told CNN the gunman opened fire within seconds.

“This guy just came out of nowhere and came out with a gun and shot people in Thousand Oaks, California,” Harrah said. “And that’s what’s really blowing my mind, it’s a really safe area.”

Reports of the shooting came in around 11:20 p.m. PT.

“I heard a gunshot, I turned around and I saw him shoot a couple more times,” California Lutheran University student Teylor Whittler told KABC. “Within a split second, everybody yelled ‘get down,’ ” she said.

Witnesses said that people dropped to the floor and hid behind bar stools in stunned silence. Others jumped over chairs and broke windows to get out of the bar.

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