A helicopter carrying international troops crashed Tuesday, killing nine service members in southern Afghanistan where troops are ramping up pressure on Taliban insurgents.
The cause of the crash in Zabul province was not immediately clear. The Taliban claimed to have shot down the helicopter, but NATO said there were no reports of hostile fire.
It was the worst chopper crash for coalition forces in four years in the rugged country where helicopters are heavily used to transport military troops spread over mountainous terrain with few roads. This year was already the deadliest for international forces since the war began in 2001.
One other coalition service member, an Afghan National Army soldier and a U.S. civilian were injured.
The nationalities of the service members who died have not been released. So far this year, 525 U.S. and NATO forces have been killed in Afghanistan, surpassing the 504 killed last year.