A court appearance is scheduled on Monday for a man accused of killing a Virginia police officer on her first day on the job.

Ashley Guindon was responding to a call on Saturday that could have become routine had she gone on to a long career in law enforcement: a domestic disturbance in a well-kept suburban neighbourhood.

But something had already gone terribly wrong inside the northern Virginia home of army Sgt. Ronald Hamilton, police said Sunday, and Guindon's brief time with the Prince William County police department came to a horrific end.

Hamilton opened fire on Guindon and two of her fellow officers, killing her and leaving the others seriously wounded, Prince William County police Chief Stephan Hudson said.

Standing stone-face next to the county's top elected official and chief prosecutor on Sunday, Hudson lauded Guindon's bravery, intelligence and compassion. The chief offered no details to reporters about what might have provoked the gunman, who worked at the Pentagon and, according to neighbours, was about to be transferred to Italy.

The fight Saturday afternoon between Hamilton, 32, and his wife, Crystal Hamilton, 29, had continued throughout the day, but it escalated after she called 911, Hudson said. Hamilton fatally shot his wife between her call to police and the officers' arrival, and the three officers were shot just after they arrived at his front door, he said.

Shooter's son safe

As quickly as the violence began, it was over, Hudson said, with Hamilton emerging from his front door to surrender as additional officers arrived. The couple's 11-year-old son was home at the time of the slayings and is being cared for by relatives, Hudson said.

Guindon, 28, died at a hospital, where the two other wounded officers — Jesse Hempen, 31, and David McKeown, 33 — were being treated on Sunday. Police did not detail their injuries. Hudson said their lives were no longer in danger but they faced long recoveries.

The incident came just hours after a picture of Guindon was posted to the department's Twitter page on Friday with a tweet that read: "Welcome Officers Steven Kendall & Ashley Guindon who were sworn in today & begin their shifts this weekend. Be Safe!"

Guindon, a former U.S. Marine Corps reservist who had a master's degree in forensic science, went through training with the department last year but left for personal reasons, Hudson said. She rejoined the department this year and was sworn in on Friday, which the department marked with a celebratory tweet.

"We were struck by her passion to do this job," Hudson said. "She did share with us when we rehired her that she felt like she wanted to do this job. She couldn't get it out of her blood. She clearly had a passion to serve others in a way that went beyond herself."

Department 'respected'

Her line-of-duty death was the fourth in the 46-year history of the department, and only the second time a county officer was slain maliciously, county officials said. The county has 446,000 residents, and Woodbridge is one of many bedroom communities popular with federal workers, the military and others who commute to Washington, 50 kilometres to the north.

"This department is revered. It's respected," said Corey Stewart, the Republican chairman of the county's board of supervisors. "She was an example of the kind of person that the department hires and the quality of the men and women who work for the department."

The county's longtime chief prosecutor, Commonwealth's Attorney Paul Ebert, said he would likely seek the death penalty against Hamilton, who was being held without bond on charges including capital murder, first-degree murder and malicious wounding and was scheduled to be arraigned Monday morning.