BUTTE COUNTY (KPIX) – More details are emerging about exactly what happened leading up to the ambush shooting of a East Bay doctor and two others over the 4th of July holiday weekend, and the suspect in custody.

It happened near Poker Flat about 10 miles outside Downieville on Friday afternoon, July 3.

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Dr. Ari Gershman of Danville was killed in the attacks and two others were injured.

KPIX 5 spoke with a witness who says he was nearby when the shooting happened. He did not want to reveal is name or show his face because he fears for his family’s safety. He says they have a handful of mining claims right outside Poker Flat, and that’s why he was at the top of the hill as people came running out of the camping area.

“Those people were pretty close to where the shootings happened. They were terrified and they said, ‘you’ve got to get out of here. There’s an active shooter,’” he said.

He says the people coming out of the campground told him it all started when a man drove into the area in on an off-road vehicle and started going through people’s campsites.

“There had been a man who was down in Poker Flat rummaging through another camper’s items and that when he questioned him, he pulled out his 9mm and shot the guy in the arm,” he said.

Campers said immediately after the first shooting, the suspect drove off up the hill and that is where the second person – a woman – was shot.

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“She said she saw him coming out in the side-by-side and she motioned to her dog, you know, get out of the way, he’s coming up, and that he didn’t say anything. That she was standing there and that as he drove by, he just aimed over and shot her in the arm,” he said.

Investigators with the Sierra County Sheriff’s Department say not long after the second shooting, the gunman drove up behind Dr. Ari Gershman and his 15-year-old son Jack who were stopped in their Jeep and started shooting when Dr. Gershman asked him for directions.

Gershman was killed and his son Jack ran for his life. He was not hurt, but was lost in the woods for 30 hours before rescuers found him by tracing his cell phone signal.

“Is there something more that could have been done in this case, and quite frankly, there didn’t seem to be,” says Butte County District Attorney Mike Ramsey. He says the shooting suspect, now identified as 40-year-old John Thomas Conway from Oroville, had some run-ins with the law recently.

He was arrested in 2019 after a family dispute and earlier this year, he was arrested again and accused of stealing a similar utility terrain vehicle to the one used during the shootings.

“There was indications he had some mental health issues though,” says Ramsey.

According to Ramsey, the suspect was also battling addiction to both methamphetamine and alcohol.

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The District Attorney also says Conway was accused of violating his probation and a bench warrant was issued about a month ago. He says due to COVID-19 concerns, probation officers weren’t as active trying to go out and make those kinds of arrests.