Authorities seek a motive in the mass shooting at an Idaho In-N-Out Burger

A driver charging his electric taxi and a former law enforcement officer who tried to intervene were among the seven people wounded in a mass shooting at an Idaho fast food restaurant that also left three people dead, according to friends and relatives of the two men.

The attack Saturday at a new In-N-Out Burger in Twin Falls ended when the gunman, identified by police as 24-year-old Chad Williams , shot and killed himself. On Monday, police were still trying to determine why Williams carried out the attack, which happened early in the afternoon in a busy shopping plaza in the southern Idaho city.

Many details about Williams' life were still unknown Monday, but an initial search of court records in Idaho and Arizona, where he used to live, didn't show any criminal cases matching his name and birth date.

Elijah Moseley, who lived across the hall from Williams in a College of Southern Idaho dorm a few years ago, described him as “an introvert” and “a pretty chill guy.”

“I was never scared or weirded out by him,” he said.

Moseley said he considered Williams a relatively close friend, though they lost touch a couple of years ago. “I’m shocked by this and sick to my stomach about this,” he said.

Detectives are confident that Williams acted alone, Police Chief Matthew Hicks said Sunday, noting that Williams’ family is cooperating fully with the investigation.

Two of the wounded were treated at a hospital and released, three were listed as stable, and two others were in critical condition, police said Sunday.

During the attack, an off-duty state trooper and a civilian fired on Williams and diverted him from the restaurant, the chief said. Police haven't disclosed their names or those of the victims, but some victims have been identified by friends and relatives. Twin Falls spokesperson Josh Palmer said Monday that police were still trying to identify next of kin.

The attack happened at an In-N-Out that opened late last month as part of the California chain’s Idaho expansion.

An employee at the burger joint was among those killed, the fast-food chain’s owner, Lynsi Snyder, said in a statement. She didn't identify the worker.

Kimberley Castaneda confirmed to The Associated Press that her brother, Christopher Claunch, was among those killed, but she declined to discuss him and the circumstances surrounding his death further.

In a Facebook post, Marcus Scott said his son Austin “A.J.” Scott was critically wounded in the attack and faces a long recovery. He said his son was shot after he moved “toward the danger” when he heard gunfire in an effort to protect others.

“We are incredibly thankful that God spared his life and that his wife and friend were there to provide immediate care until he could get to the hospital," he wrote.

Marcus Scott said in a message to the AP on Monday that his son used to work as a law enforcement officer for the Twin Falls police and the Idaho State Police. But he declined to comment further on his son’s actions, saying it is his son's story to tell.

Terry Dudley, a driver for North Star Taxi, was shot as he was charging one of the company’s Teslas in a parking lot next to the In-N-Out Burger, said James Palmer, who owns the taxi service and is Dudley’s friend.

Palmer said Dudley called him to tell him he was shot after he couldn’t get through to 911. He said Dudley was flown to a hospital in Boise and remained there Monday with serious injuries, he said.

“It’s a lot man,” Palmer said. “It’s daunting, to say the least, to even try to gather the scope of all this. It’s been absolute chaos."

He said Dudley was “kind of like my right hand.”

Williams attended the College of Southern Idaho from August 2022 and December 2023, according to the school's president, L. Dean Fisher. He didn’t graduate or earn a certificate from the school, which has about 10,000 students.

Williams served in the student senate but was unanimously impeached by his fellow senators in February 2023. Moseley, who served as the senate pro-tempore at the time, said Williams was ousted because he wasn't very active or engaged in student government.

Associated Press reporter Jamie Stengle contributed to this report.