FLAGSTAFF, Ariz. — A northern Arizona police officer killed over the weekend was shot repeatedly at close range by a domestic violence suspect after calmly asking the man if he could pat him down for any weapons, authorities said Sunday.

Flagstaff Officer Tyler J. Stewart, 24, died Saturday at Flagstaff Medical Center shortly after being shot multiple times.

Stewart had responded to a domestic violence call from the suspect’s girlfriend at about 11 a.m. Saturday, police Sgt. Margaret Bentzen said. The woman told the officer she had an argument with Robert W. Smith, 28, and that he had left the area.

Stewart later found Smith at an apartment complex where he questioned the man but “at no time did the conversation become confrontational,” Bentzen said in a statement.

When Stewart asked the suspect if he could check him for weapons, Smith pulled a gun from his pocket and opened fire on the officer from about 2 feet away, according to the statement.

Stewart did not have time to return fire, and Smith continued to shoot the officer repeatedly even after he had sustained serious wounds and was on the ground, Bentzen said

Smith then walked away and fatally shot himself, she said. He died at the scene.

The investigation remained ongoing. Authorities said Smith was arrested in 2009 by Flagstaff police for a domestic violence incident.

Stewart is the second Flagstaff police officer to be killed in the line of duty. On June 21, 2000, Officer Jeff Moritz, 30, was killed after he pulled over a teenager who was driving around his neighborhood in a truck playing loud music.

Stewart had worked at the department for less than a year. He was a graduate of Boulder Creek High School in Anthem, Ariz., near Phoenix, and later attended Concordia College in California, police said.

“This is an enormous tragedy for our department and the family of our officer. We are a very close-knit organization, and know that all members of the Flagstaff Police Department are grieving at this time. With that being said, all of the men and women of the Flagstaff Police Department extend our prayers and condolences to the family of our Officer Tyler Stewart,” Chief Kevin Treadway said in a statement.

“It is heartbreaking to lose one of our officers,” Mayor Jerry Nabours said.  “We collectively mourn for his family and the entire department.”

Hundreds gathered at a candlelight vigil on Sunday evening outside the Flagstaff Police Department at the agency’s Officer Down Memorial Statue, KPHO reported.

A makeshift memorial of flowers, candles and balloons was growing larger as members of the community added to it. Children used chalk to draw pictures and to write messages of thanks for the officers.

The shooting was the second one of a police officer in northern Arizona in three months. In October, a tribal police officer of the Navajo Nation was shot in the face during a shootout with a suspect in the town of Kaibeto, about 75 miles north of Flagstaff. The officer survived.