A small Pennsylvania community is reeling after three decorated detectives were gunned down in an ambush. They were serving a warrant in a stalking case tied to a woman’s armed ex-boyfriend.

On Wednesday afternoon, members of the Northern York County Regional Police Department entered a home in North Codorus Township to continue their search for Matthew Ruth, 42, who had been stalking his ex-girlfriend with an AR-15 rifle.

What the officers didn’t know was that Ruth had already entered the woman’s home after she and her mother fled for safety. Inside, he killed the family’s black Labrador and waited for police to arrive.

The moment detectives opened the unlocked door, Ruth unleashed a hail of bullets from an AR-15-style rifle fitted with a suppressor. The ambush lasted about two minutes.

Detective Sergeant Cody Becker, and Detectives Mark Baker and Isaiah Emenheiser were fatally struck. Two other officers, another Northern York detective and a York County sheriff’s deputy, were critically wounded before Ruth was killed in a final exchange of gunfire near the roadway.