(FARMINGTON, N.M.) — At least 150 rounds were fired by an 18-year-old gunman and responding officers during an apparently random shooting in a neighborhood in northwestern New Mexico on Monday, authorities said.

Three people driving through the area were killed shortly after the gunman opened fire at approximately 10:56 a.m. local time in a residential area of Farmington, about 15 miles south of the border with Colorado, police said.

The suspect — identified by police Tuesday as Beau Wilson, a student at Farmington High School — was shot dead by officers at 11:06 a.m., police said.

A motive remains unclear at this stage in the investigation, police said.

“This incident appears to be purely random,” Farmington Deputy Chief Kyle Dowdy told reporters Tuesday. “It had no specific targets or motives to be identified at this time.”

Most of those shot were driving through the area, Farmington Deputy Chief Baric Crum said. Those killed included a woman in her 90s and the victim’s daughter, who was in her 70s, Crum said. The third victim was also in her 70s, he said.

The deceased victims were identified by police Tuesday as Shirley Voita, Melody Ivie and Gwendolyn Schofield.

Two of the victims were pronounced dead at the scene, while a third died at a hospital, police said. Six other victims, including two police officers, were treated at San Juan Regional Medical Center and have since been released, the hospital said. Other victims were treated at the scene, authorities said.

Police have not found any links between the suspect and the victims, police said.

“We’ve discovered nothing that leads us to believe that this suspect knew any of the people,” Dowdy said. “That we’re pretty confident in, because this was pretty random. Because the shooting was arbitrary and up and down the street.”

The suspect walked through the neighborhood, shooting “indiscriminately” at houses and cars, Dowdy said. At least six houses and three cars were hit by gunfire over the course of a nearly quarter-mile crime scene, Dowdy said.

Hundreds of 911 calls came in during the incident, Dowdy said.

Four officers engaged the suspect in a firefight, and the suspect was ultimately killed, Crum said.

At least 150 rounds have been found at the crime scene so far, though investigators do not know who fired what yet, Dowdy said.

“We’re still counting — that’s legitimately going to go up,” he said. “At this point, we’ve got approximately 150 [rounds] exchanged between everyone.”

One of the wounded officers was shot while responding to the scene, while the second was shot during the firefight with the gunman, Crum said. The two injured officers — one from the Farmington Police Department and one from New Mexico State Police — have since been released, officials said.

The suspect was armed with multiple firearms, including an assault-style rifle, police said. Dowdy said the suspect purchased one firearm in November 2022, a month after he turned 18, and police believe he obtained the others from a family member.

Wilson had “minor infractions” as a juvenile, though nothing in his history would have led him to be on their radar, Dowdy said.

Farmington Mayor Nate Duckett thanked residents for their help in supporting law enforcement amid the response.

“There were many acts of bravery that occurred yesterday,” Duckett said.

ABC News’ Ivan Pereira, Matthew Fuhrman and Morgan Winsor contributed to this report.

Copyright © 2023, ABC Audio. All rights reserved.