Idaho In-N-Out shooting leaves 3 dead: What we know about the suspected gunman

BOISE, Idaho - The suspect in the fatal shooting at a newly opened In-N-Out Burger in southern Idaho died from a self-inflicted gunshot wound, police said Sunday, as investigators said they believe he acted alone in the attack.

What we know about the shooter, Chad Williams

What we know:

Twin Falls Police Chief Matthew Hicks identified the gunman as 24-year-old Chad Williams during a Sunday news conference. Authorities said Williams opened fire Saturday afternoon at the restaurant in Twin Falls, killing three people and injuring seven others before taking his own life.

RELATED: In-N-Out Burger shooting leaves multiple dead in Idaho

Police said they are confident Williams was the only shooter. Investigators have not released a motive and said the investigation remains ongoing.

Officials said two of the injured victims have been treated and released from the hospital. Three others remain hospitalized in stable condition, while two remain in critical condition.

Hicks credited an off-duty Idaho State Police trooper and an armed citizen with helping prevent the attack from becoming even more deadly.

"We believe their actions helped drive the suspect away from the scene, preventing further casualties," Hicks said.

One of the people killed was an In-N-Out employee, according to the company's owner.

"My heart is broken, my chest is heavy, my eyes burn from the tears I've shed. We lost one of our beautiful Associates tonight," In-N-Out owner Lynsi Snyder wrote in a social media statement early Sunday.

"In-N-Out will be mourning with the families and praying for them as they tread through a very painful season," Snyder said.

What we don't know:

Snyder did not identify the worker. Officials were still trying to notify relatives of victims and so were not yet releasing the names, ages or other details about the people hurt in the shooting, Twin Falls spokesperson Josh Palmer said Saturday.

Police who responded to the shooting found the body of the suspected gunman in an area near the restaurant, Palmer said. He did not know if the suspect was included in the fatality count. Some of the people injured were in critical condition, Palmer said.

Police were still trying to determine the shooter's motive.

The backstory:

The shooting unfolded around 2 p.m. Saturday at the recently opened restaurant in a busy shopping plaza. Twin Falls police said officers responding to the scene later found Williams dead from what investigators determined was a self-inflicted gunshot wound.

Witness Lane Koehn said he was stopped at a nearby traffic light when he saw a man carrying what appeared to be an AR-style rifle emerge from the drive-thru. Koehn said another man armed with a handgun returned fire at the shooter.

Koehn also helped an employee who had been shot in the chest after another worker dragged her across the parking lot.

"She was pretty bad off, but I don't know. I hope she made it," Koehn said.

He said police instructed people to evacuate because the shooting was still active and estimated the gunman fired at least three or four rounds. He said it was not clear whether anyone was specifically targeted.

Video recorded by a driver across the street appeared to show the suspect, dressed in black and carrying a long rifle, approaching a white vehicle, opening the driver's-side door and then accessing the trunk before the person filming drove away fearing additional violence.

The In-N-Out restaurant had opened July 24 as part of the California-based chain's expansion into Idaho.

The FBI is assisting the Twin Falls Police Department with the investigation and has asked anyone with photos or videos from the shooting to contact investigators.

Twin Falls, a city of about 56,000 residents, is located roughly 130 miles southeast of Boise and about 75 miles north of the Nevada border.