KABUL (AP) -- NATO forces say six Afghan police officers have been beheaded by insurgents in northern Afghanistan after a militant attack.

The military coalition said in a statement issued today the militants attacked a number of government buildings, including a police checkpoint. The insurgents overran the checkpoint Tuesday and killed the officers inside by cutting off their heads.

And Afghanistan's Defense Ministry says an Afghan soldier shot and killed two U.S. civilian trainers at an army base in northern Afghanistan before being shot dead. An Afghan soldier caught in the crossfire also died.

The ministry says an argument started during a weapons-training exercise Tuesday and the Afghan soldier turned his gun on the Americans.

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