Ten out of a total of 12 crew members died when two US Marine Corps helicopters crashed off the coast of Djibouti on Friday, the US military said today.
Eight of them were Marines and two were Air Force Airmen, a statement said.
The small Red Sea state of Djibouti is a hub of US counterterrorism operations in the region.
Two crew members were rescued after the crash, injured but in a stable condition.
"The Department of Defense confirmed the deaths of 10 CH-53E crew members as a result of the crash that occurred off the coast of northern Djibouti Friday," the statement said.
The US military earlier said the cause of the crash was not known, but also referred to it as an accident. It did not say if the aircraft collided or how they went down.
The two Marine transport helicopters crashed during a training mission, each of them carrying six crew members.
On Saturday, the military said all of them had been accounted for, but declined to say whether the 10 who had been missing were dead or alive, pending notification of their families.