(Adds comment from neighbor on CNN, paragraphs 12-13)
By Gabriella Borter and Jonathan Allen
Nov 8 (Reuters) - The man suspected of killing 12 people in a Southern California bar was a decorated Marine Corps machine gunner who served in Afghanistan and later exhibited signs of instability that came to the attention of police, authorities said on Thursday.
Suspect Ian David Long, who was found dead of an apparently self-inflicted gunshot wound, was 28 years old and lived with his mother in Newbury Park. A prosperous suburb of Californian bungalows and tidy front lawns, Newbury Park is about 4 miles (6.4 km) from the Borderline Bar & Grill where the shooting took place on Wednesday night.
In April, his mother, Colleen Long, told Richard Berge, a neighbor who occasionally took care of her dogs, that she was worried that her son might take his own life.
"I just know she lived in hell in there with him punching holes in the walls and stuff," Berge told Reuters.
Long's mother, Colleen Long, has worked for more than eight years as an analyst for Dole Food Co, according to her social media profiles.
Long joined the Marine Corps in 2008 and rose to the rank of corporal before leaving active service in 2013, Joseph Butterfield, a Marine Corps spokesman, said in an email.
He served in the war in Afghanistan for seven months beginning in late 2010, mainly as a machine gun operator, and was awarded multiple ribbons, commendations and medals, the Marine Corps said.
He was awarded two Navy unit commendations as a member of a unit that display "outstanding heroism" in battle.
"The Marine Corps extends its deepest condolences to the families of the victims in this senseless tragedy," Butterfield wrote in the email.
After leaving the Marine Corps, Long was a student at California State University, Northridge and last attend in 2016, the school said in a statement. It did not say what Long had studied.
At a news conference on Thursday, Ventura County Sheriff Geoff Dean said police had responded to a minor disturbance call at Long's house in April.
"He was somewhat irate, acting a little irrationally," Dean said. The police called in a team of mental health specialists who decided that Long did not qualify to be involuntarily detained for mental health evaluation under state law.
"They couldn't get him to come out, so it was like a standoff for four or five hours," Berge said.
An American flag hung on the garage at Long's home on Thursday as law enforcement gathered outside. A red pickup truck was parked in the driveway.
According to public records, Long appeared to be the grandson of H. Daryl Foley, a former U.S. Navy commander who spent 30 years in the service and died in 2010, according to a published obituary. (Reporting by Gabriella Borter and Jonathan Allen in New York; Additional reporting by Mike Blake in Newbury Park, California, Gina Cherelus in New York and Bernie Woodall in Ft. Lauderdale, Fla.; Editing by Jeffrey Benkoe and Grant McCool)
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