WASHINGTON (AP) — Six U.S. service members have been killed in Afghanistan, after a helicopter with engine trouble went down in the southern part of the country. That word comes from U.S. and NATO officials.

According to U.S. defense officials, one person on board the aircraft survived with injuries.

NATO says the crash is under investigation, and that there was no insurgent activity in the area. An official in Washington says investigators are looking at an "engine failure."

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