A least two people were killed and seven wounded in eastern Afghanistan when police clashed with demonstrators.
Several thousand protesters were demonstrating against the killing of three civilians in the area by foreign forces in an overnight raid.
The protesters said five civilians had also been detained in the raid.
An official for NATO in Kabul said he was not aware of the raid.
The U.S. military said all those killed were militants and the target of its raid was “a foreign fighter network”.
More than 700 civilians have been killed during operations by foreign troops while hunting Taliban-led insurgents in Afghanistan in recent years.