Kabul, April 9 (Inditop.com/AKI) A military helicopter crashed in southern Afghanistan, killing at least three US service members and one civilian employee, a statement from NATO-led forces said Friday.

The cause of the crash of the Air Force CV-22 Osprey was not known, said the International Security Assistance Force statement, although a report quoted a Taliban spokesman as saying the aircraft was shot down.

Several other soldiers suffered injuries in the crash late Thursday night.

NATO is leading an offensive in southern Afghanistan to clear the area of Taliban militants.

The CV-22, which conducts long-range infiltration and re-supply operations for the US military, went down seven miles west of the city of Qalat, the capital of Zabul province.

Zabiullah Mujahid, spokesman for the Taliban in the region, was quoted as saying Taliban fighters shot down the aircraft. Another spokesman, Qari Yoseph, also claimed responsibility and said that 30 Americans had been killed.