THOUSAND OAKS (CBSLA) — Ian David Long, a Marine Corps. veteran, was identified as the shooter who killed a dozen people, including a sheriff’s sergeant, late Wednesday at a Thousand Oaks bar hosting a “college country night.” Long then turned the gun on himself, authorities said.

Ventura County Sheriff’s deputies responded to reports of shots fired at Borderline Bar and Grill, located at 99 Rolling Oaks Drive, around 11:20 p.m. Wednesday. The bar was hosting its weekly country music night for college students, according to the bar’s website.

Witnesses described the suspect as a man who possibly had a beard and was wearing a trench coat and had a scarf on his face. Ventura County Sheriff Geoff Dean said the suspect was deceased inside the bar when backup arrived. A motive has not been determined, but investigators believe the attack was planned.

“There’s fire escapes, and the patrons exited out of all those,” Dean said. “They ran out of back doors, they broke windows, they went through windows, they hid up in the attic, they hid in the bathroom.”

Dean said 12 people were killed, including 54-year-old Ventura County Sheriff’s Sgt. Ron Helus. He was a 29-year veteran who was set to retire next year, Dean said. Helus is survived by his wife and son.

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“Ron was a hardworking, dedicated sheriff’s sergeant. He was totally committed, he gave his all and tonight, as I told his wife, he died a hero. He went in to save lives, to save other people,” Dean said.

Another eight to 15 other people appear to have suffered minor injuries, Dean said.

“It’s my understanding, and again, don’t hold me to this, that there’s one other minor gunshot injury,” Dean said. “And there’s somewhere between eight and 15 other injured, mostly cuts from jumping out of windows, diving under tables. They’re relatively minor compared to everything else.”

Dean added that the shooting appeared to be random in nature, and it did not appear that Long was targeting specific people inside the bar.

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In a news conference, Dean said the 28-year-old Marine Corps. veteran was visited by the Ventura County sheriff’s crisis intervention team in April after a call of a “subject disturbing” at his home in nearby Newbury Park. Long, who was also a Cal State Northridge student, was never placed on a mental health hold, and Dean said Long may have been suffering from PTSD.

Local and federal authorities were at Long’s home in the 800 block of Fowler Avenue in Newbury Park waiting for a search warrant so they could enter the home. His mother is reportedly still inside the home and speaking to investigators.

Pepperdine University, which lowered its flags to half staff Thursday, confirmed several of its students were at the bar during the shooting. California Lutheran University, located less than five miles away, canceled classes Thursday and Friday.

Witnesses said the gunman shot a bouncer and a cashier before he opened fire near the dance floor. He reportedly threw smoke bombs into bar, where hundreds of people were dancing to country music, before opening fire with a Glock 45-caliber handgun fitted with an extended magazine.

Some people who were inside the bar said they had survived the deadly mass shooting at the Route 91 Festival in Las Vegas last year.

A witness who was inside the bar during the shooting said she heard “very, very loud gunshots.”

“There were people in the middle dancing and just hanging out and having a good time and you hear that and you just know something’s up,” Erika Sigman said. “In this community, it’s very hard for me to comprehend it because I’ve been here all my life and to think that – I’ve never experienced it, I’ve just never experienced it.”

One couple told CBS2’s Tom Wait that their daughter had been injured in the shooting.

“She was probably on the [dance] floor when this was going on, because she comes here every Wednesday night,” the victim’s father said. “Things are a little sketchy – we don’t have a lot of information right now.”

Another witness said there was numerous shots fired inside the bar.

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A witness who was on the patio area of the bar said she was saved by a stranger after gunshots rang out.

“A guy who I don’t even know who had seen me there was like, ‘Get down.’ He threw me under one of the tables and then you couldn’t see anything because I guess there was smoke. And then one of the guys who was there started throwing tables out the window and they picked us up and they threw me and my girlfriend out the window. They carried us and then I reunited with my friends, and I was lucky to get out. I was only there for a good 10 minutes but I just – there’s like no words. Those are my people and it’s just not fair, it’s not fair,” she said.

President Trump offered praise for law enforcement’s response.

I have been fully briefed on the terrible shooting in California. Law Enforcement and First Responders, together with the FBI, are on scene. 13 people, at this time, have been reported dead. Likewise, the shooter is dead, along with the first police officer to enter the bar…. — Donald J. Trump (@realDonaldTrump) November 8, 2018

….Great bravery shown by police. California Highway Patrol was on scene within 3 minutes, with first officer to enter shot numerous times. That Sheriff’s Sergeant died in the hospital. God bless all of the victims and families of the victims. Thank you to Law Enforcement. — Donald J. Trump (@realDonaldTrump) November 8, 2018

An emergency information hotline has been set up to help locate people involved in the shooting at 805-465-6650. A reunification area has been established at Thousand Oaks Teen Center, located at 1375 E. Janss Rd.

The FBI and ATF are assisting with the investigation.