Afghan police officer kills 2 U.S. troops

KABUL, Afghanistan (AP) — A police officer opened fire on U.S. and Afghan forces inside a police headquarters in eastern Afghanistan on Monday, sparking a firefight that killed two U.S. troops and two other Afghan policemen. The attacker was also killed in the shootout, officials said.

The incident in Wardak province was the latest in a series of insider attacks against coalition and Afghan forces that have threatened to undermine their alliance at a time when they need to work increasingly close together in order to hand over responsibility as planned next year.