gunman opened fire at a bar in the US state of California on Thursday (November 8) killing 12 people, including a police officer.

The gunman, identified by authorities as Ian David Long, 28, was also found dead in the office of the Borderline Bar and Grill, located in Thousand Oaks, a suburb about 40 miles from Los Angeles, apparently having shot himself.

The officials have said that the shooter was a Marine Corps veteran and had apparently fired at random with a .45-caliber Glock handgun with an extra-capacity magazine. There was no known motive.

Obviously he had something going on in his head that would cause him to do something like this, Ventura County Sheriff Geoff Dean said. Obviously he had some sort of issues.

The Borderline is popular with university students and was hosting College Country Night.

News channel ABC News spoke to witnesses who said that the shooter first fired several shots from a handgun before tossing smoke bombs and then opening fire again.

Another witness said that the gunman fired 30 shots. “He shot a lot, at least 30 times. I could still hear gunshots after everyone left,” the unnamed witness told the newspaper Los Angeles Times.

SCENE LIKE HELL

Asked what the scene inside the bar was like, Ventura County Sheriff Geoff Dean said, Like … hell. Earlier he had described it as a horrific scene in there. There is blood everywhere and the suspect is part of that.

Long first shot a security guard outside the bar, stepped inside and resumed shooting, Dean said. Witnesses said Long had used smoke bombs to create confusion but Dean said that had not been confirmed.

Dean, speaking on his last day before retirement, said he had been told 150 to 200 people were in the Borderline at the time and that it could have been much, much worse”.

Dean estimated 10 to 15 people, including one with a gunshot wound, had gone to hospitals. He said he thought their injuries were minor, and that most of them were likely injured as they escaped, some by breaking windows.

Meanwhile, President Donald Trump called the shooting “terrible” and thanked the law enforcement for a quick reaction.

“…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,” tweeted Trump.