26-year-old Tara O'Sullivan of Pleasant Hill was shot and killed Wednesday after answering a call at a Sacramento home where a domestic dispute was reported. O'Sullivan, who just graduated from the police academy in December, was the first police officer killed in the line of duty in Sacramento in 20 years.

The domestic dispute, reported before noon on Wednesday, was between a man and a woman on the 200 block of Redwood Avenue in North Sacramento. O'Sullivan answered the call with her training officer, and as ABC 7 reports, she was shot by the suspect with a rifle around 6 p.m. while helping the woman involved in the dispute move out of the home. The suspect then continued shooting at officers, forcing them back to a safe distance. They ultimately had to conduct a rescue operation with an armored vehicle to extract O'Sullivan about 45 minutes later.

As the Chronicle reports, the 26-year-old rookie later died at UC Davis Medical Center.

Sacramento police spokesman Sgt. Vance Chandler tells the Chronicle that officers at the scene had to create “very, very big perimeter” due to the long range of rifle fire. Nearby residents also had to be evacuated. The suspect reportedly continued firing the rifle regularly for hours, barricading himself in the home for hours after the shooting, until finally surrendering just before 2 a.m. Thursday.

O'Sullivan and her training officer had reportedly met with the woman involved in the domestic disturbance at a separate location at 3:30 p.m. Wednesday. They then proceeded back to the home on Redwood Avenue at 5:30 p.m. to escort the woman as she gathered her belongings. The male suspect fired on the officers as they were escorting the woman out, and no one was injured except O'Sullivan.

As KPIX/CBS SF reports, O'Sullivan was a 2011 graduate of College Park High School in Pleasant Hill, and attended Sacramento State before entering the police academy. She was only six months into training as of last night. Per ABC 7, friends and colleagues described O'Sullivan as "having a bubbly personality and [she] was always willing to help."

Sacramento Mayor Darrell Steinberg gave an emotional press conference early Thursday, saying to O'Sullivan's family, "As the father of a 25-year-old daughter, I grieve with you."

A total of five officers discharged their weapons during the six-hour ordeal.

The suspect in the shooting has not been publicly identified, but he is in custody.

As the Chronicle reports via local officials, "Officers with the Homicide Detectives, Internal Affairs and Crime Scene Investigation units will remain at the scene for several days to conduct an officer-involved shooting investigation."