Before authorities said he opened fire at a Thousand Oaks, Calif., bar, killing 12 people Wednesday night, Ian David Long was known to neighbors in his Newbury Park neighborhood as a troubled ex-Marine who appeared to have serious mental health problems.
Dressed in black, Long, 28, drove his mother's car to the Borderline Bar & Grill, where he threw smoke bombs and rained bullets on a crowd of 150 to 200 people, law enforcement officials said.
Ventura County Sheriff Geoff Dean said officials discussed whether Long suffered from post-traumatic stress disorder, or PTSD.
He said his department had had several interactions with Long, including a visit to his home in April for a complaint of disturbing the peace. Deputies at the time said Long was irate and acting irrationally, Dean said. They called in mental health professionals to evaluate him, and they concluded he did not need to be taken into custody.
Long was the victim of a battery at a different Thousand Oaks bar in January 2015, Dean said.
Neighbor Richard Berge, 77, said Long was known to kick in the walls of the home he lived in with his mother.
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"She's a very sweet woman, but she had a lot of problems with the son," Berge said. "I just know he tore the house up."
Tom Hanson, 70, also lived near the Longs.
Earlier this year, sometime in April, Hanson called police when he overheard Ian Long one morning tearing the house apart. Hanson was worried that Long would hurt himself.
"I am not surprised, but I'm shocked," Hanson said.