NATO and Afghan forces killed 22 Taliban fighters in separate clashes in a southern Afghan province where hundreds of militants have gathered, a police official said Tuesday.

More than 300 British marines cleared "a stronghold of Taliban extremists" around a hydroelectric dam in the Kajaki district of Helmand province — a region that has been the target of Taliban attacks, NATO's International Security Assistance Force said.

Provincial police chief Ghulam Nabi Malakhail said 15 Taliban fighters were killed in three days of fighting. Lt. Col. Angela Billings, an ISAF spokesman, said there was an exchange of fire for much of the day Monday but she couldn't confirm the Taliban death toll.

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Taliban fighters shot at the British troops with small arms fire and rocket propelled grenades, ISAF said. Attack helicopters provided air support.

ISAF troops in the region have been clearing compounds for the past six weeks, ISAF said. Civilians have fled the area, forced from their homes by Taliban fighters, it said.

Elsewhere, fighting in the Musa Qala district of Helmand province killed seven Taliban militants, including a commander named Mullah Tohr Jan, Malakhail said. He said NATO and Afghan forces suffered no casualties.

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