Story highlights Officer Ashley Guindon, 28, was on her first shift as a Prince William County police officer

She was fatally shot while responding to a domestic call in Woodbridge, the chief says

Ronald Hamilton is charged with killing Guindon and wounding two other officers after allegedly killing his wife

(CNN) A police department in a Washington suburb is mourning an officer who was killed during her first day on the job.

Ashley Guindon, 28, of the Prince William County Police Department was fatally shot Saturday in Woodbridge, Virginia, while answering a domestic call in which two other officers were wounded and the suspect's wife was killed, county police Chief Steve Hudson said at a news conference on Sunday.

Guindon had taken the oath of office on Friday.

Ashley Guindon was sworn in as an officer on Friday.

"The Prince William County Police Department is in deep mourning," Hudson said. "This is a sad day for everybody in this room, a sad day for law enforcement."

Ronald Williams Hamilton, 32, is accused of shooting the three police officers as they approached the front door of his house about 5:30 p.m. Saturday, Hudson said. He surrendered to backup officers who arrived after the three officers were shot, Hudson said.

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