KABUL, Afghanistan — An Afghan policeman opened fire on American troops at a police station, killing an American soldier and wounding three, officials said yesterday.

An American commander said American forces in the station in eastern Afghanistan then killed the policeman.

“Initial reports suggest that a rogue ANP [Afghan police] official turned on our forces and shot and killed one of our soldiers, the commander of Task Force Currahee in eastern Afghanistan, Colonel John “Pete” Johnson, said.

The shooting took place in Paktia province Sunday after American troops and Afghan police brought suspected militants to the station. The policeman wounded three American soldiers, one of the detainees, and an Afghan interpreter working for the Americans, officials said.

Three detainees escaped during the confusion, Colonel Johnson said. When asked whether the Taliban or another militant group had infiltrated the police, he said it was a possibility.

“I think that’s certainly an assumption that you could make but at this point, I can’t confirm it,” Colonel Johnson said. “I don’t know what the motivations were for the ANP to turn on our forces and shoot them and shoot the detainee. Quite frankly this is way out of the norm. … This is the first incident of its kind.”

An earlier statement from NATO’s International Security Assistance Force said there was an “altercation” at the station during which an Afghan officer and a NATO soldier were killed. But it did not include any details about how the shooting happened.