Three police officers were shot dead and two others were critically wounded in Pennsylvania in a confrontation with a gunman who was fatally shot by police, officials said.
The shooting occurred in Codorus Township, a York County community in southeastern Pennsylvania, when the officers involved returned to the scene of some earlier police work, state police commissioner Colonel Christopher Paris said.
"They were there to follow up on an investigation that began yesterday," he told reporters at a news conference hours later. He declined to elaborate on the circumstances, except to characterise the investigation as "domestic-related".
Three officers died and two others struck by gunfire were taken to a nearby hospital, where they were in critical but stable conditions.
At least one local news media outlet reported the officers were attempting to serve a search warrant when shots were fired.
Mr Paris said the shooter was shot to death by police. The suspect was not publicly identified and authorities declined to immediately reveal the law enforcement agencies to which the officers belonged.
Governor Josh Shapiro asked for prayers for the families of the victims and said: "This is an absolutely tragic and devastating day for York County, for the entire commonwealth of Pennsylvania."
"It's important for you to know that these families who are grieving right now ... how proud they are of their loved ones who put on the uniform to keep us safe," he said.
Mr Shapiro also acknowledged he had received a call from US Attorney General Pam Bondi offering whatever federal support was necessary.
