California bar shooter had been a Marine, lived with his mom

THOUSAND OAKS, Calif.—The gunman who killed 12 people at a country music bar in a Los Angeles suburb was a former military machine gunner who was interviewed by mental health specialists months ago after a neighbor reported a disturbance.

Ian David Long, 28, apparently killed himself after the Wednesday attack. He had joined the Marines and gotten married young. Within several years, he left the military and divorced. Later, he enrolled at a university and most recently lived with his mother in a home where neighbors said they could hear aggressive arguments.

Long's service began when he was 18 and lasted nearly five years, including a seven-month tour in Afghanistan, according to the Pentagon. He was honorably discharged with the rank of corporal in 2013.

In April, a neighbor called authorities to report loud noises coming from the house that Long shared with his mother in a Thousand Oaks neighborhood of well-manicured lawns and homes.

Deputies found Long "was somewhat irate, acting a little irrationally" and called in a mental health specialist, Ventura County Sheriff Geoff Dean said. That specialist assessed Long but concluded he couldn't be involuntarily committed for psychiatric observation.

"The mental health experts out there cleared him that day," Dean told reporters Thursday, less than 12 hours after the Wednesday night massacre.

They also were concerned that Long might be suffering from post-traumatic stress disorder, Dean said, "basing that (on) the fact that he was a veteran and had been in the Corps."

Long's only other contact with authorities came after a traffic collision and after he alleged he was the victim of a violent encounter in 2015 at another bar in Thousand Oaks, Dean said.

A next-door neighbor said he called authorities about six months ago when he heard loud banging and shouting come from Long's ranch-style home.

"I got concerned, so I called the sheriffs," neighbor Tom Hanson said outside his home Thursday as federal and local law enforcement officers searched Long's house, where an American flag flew over the garage. "I was concerned because I knew he had been in the military."

Hanson described Long as an introvert who never caused him problems and said he was "dumbfounded" by the massacre.

Another neighbor described frequent, aggressive shouting between Long and his mother, especially over the last year. About 18 months ago, Don and Effie Macleod heard "an awful argument" and what he believes was a gunshot from the Longs' property. Don Macleod said he did not call police but avoided speaking with Ian Long.