The statement said the cause of the crash is under investigation but that preliminary reports do not indicate it was caused by enemy fire.
However, the Taliban promptly claimed to have shot down the helicopter in eastern Logar province, causing many fatalities.
Taliban spokesman Zabiullah Mujahid said in a statement to media that the insurgents downed a U.S. Chinook helicopter at around 1 a.m. during fighting with the “invaders and their hirelings.”
The U.S military dismissed the Taliban claim as false.
Wednesday’s crash brought the number of U.S. deaths in Afghanistan this year to 19. There have also been three non-combat deaths this year. More than 2,400 Americans have died in the nearly 18-year war.
The U.S. military statement added that in accordance with U.S. Department of Defence policy, the names of the service members killed in action are being withheld until 24 hours after notification of their next of kin is complete.