A gunman killed three people and wounded others in a shooting at an In-N-Out restaurant in Twin Falls, Idaho, on Saturday before fatally shooting himself, police said.

Police identified the gunman Sunday as Chad Williams, 24.

The circumstances of the shooting, which occurred at around 2:30 p.m. Saturday, as well as a possible motive remained under investigation, Twin Falls Police Chief Matthew Hicks said Sunday at a news conference.

“We are that confident Mr. Williams acted alone,” Hicks said.

Police responded to the area of the restaurant, known for its burgers and milkshakes, after multiple 911 calls were made reporting gunfire at around 2:29 p.m., Hicks said.

“Dispatchers could hear screaming and reports of gunshots in the background,” he said.

In addition to the three victims killed, seven others were injured, two of whom remained in critical condition Sunday, Hicks said.

Police did not release the identities of the victims who were killed because family notifications were being made, he said.

Lynsi Snyder, the president of In-N-Out Burger, said a worker was among those killed.

“She was taking care of our most important asset — our customers, and her life was taken by a disgusting human who doesn’t value the lives of others or his own,” Snyder said. She added: “He shot both on our property and off and ended his life shortly after he took the precious lives of our associate and customers, innocent people who never saw it coming.”

City, county and state authorities responded to the restaurant on Blue Lakes Boulevard North after reports of an active shooter, police said.

The area is also the location of multiple major retailers and a movie theater complex. Hicks said hundreds of potential witnesses were expected to be interviewed.

An armed bystander and an off-duty state police officer who happened to be there returned fire at the shooter, which Hicks called heroic actions that drove the gunman away and likely prevented more casualties.

A shelter-in-place order was issued for the area, which was later lifted. A nearby Chick-fil-A said it was closing Saturday as a precaution.

“Out of an abundance of caution, Chick-fil-A Twin Falls will be closed for the remainder of today,” the restaurant said.

Magic Valley Mall nearby was closed and people inside were told to stay put, a public safety employee there said earlier Saturday afternoon.

The In-N-Out location, the fourth in Idaho, opened July 24, according to a news release from the California-based chain.

Haley Dodaro was approaching the In-N-Out location to get lunch with her mother on Saturday just after the shooting happened. She told NBC News that they were circling the buildings to get into the drive-thru at the time when she saw people running across the road.

Sources: https://www.nbcnews.com/news/us-news/dead-injured-shooting-twin-falls-idaho-rcna590420