Investigators knocked on doors of surrounding residents to find out what they may know about Long. One neighbor who knew Long said he was a veteran who suffered from PTSD. She said, "I don't know what he was doing with a gun."
Others said Long lived at the home with his mother. Richard Berge, a friend and neighbor Long's mother, said Long's mother was worried about her son.
"He wouldn't get help," Berge said.
Dean said Long was in the United States Marine Corps. The USMC released Long's service record, detailing that he served from 2008 to 2013, deploying to Afghanistan from Nov. 16, 2010 to June 14, 2011. His ranking was a corporal as a machine gunner, the the USMC said.
Long had several interactions with the sheriff's department over the years, Dean said. These incidents include a traffic collision, a traffic citation as well as an instance in which Long was a victim of battery at a local bar in 2015.
Dean also described an incident In April, when deputies were called to his Newbury Park home regarding a disturbance.
"He was somewhat irate, acting a little irrationally. They called out our crisis intervention team, our mental health specialist," Dean said.
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https://abc7.com/thousand-oaks-shooting-suspect-what-we-know/4645948/