Six US service members have been killed in a helicopter crash in southern Afghanistan, according to officials.
One person on board the Black Hawk UH-60 was injured, but survived the crash in the southern Zabul province.
The aircraft was an Army helicopter from an Army unit, but officials have not yet confirmed the identities nor the service branches of the individuals, an official said.
A statement issued by the Nato international military coalition said the crash was under investigation and stressed there was no insurgent activity in the area at the time.
In Washington, an official originally said the helicopter had experienced engine failure before the crash, but later said that it was unclear whether that was the case.
Deputy Governor of Zabul Mohammad Jan Rasoolyar said the helicopter came down in the remote Shajau district.
This year, 109 members of the US military have died in Afghanistan, from a total of 139 in the coalition.
The death toll has dropped significantly since the coalition handed over responsibility for security to Afghan forces last summer. By comparison, 394 foreign troops died last year, including 297 Americans.
Coalition troops are now training and assisting their Afghan counterparts.
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