All 14 American soldiers on board a U.S. helicopter have been killed in a crash in northern Iraq.
The military says the Black Hawk helicopter was one of two taking part in a nighttime operation. A statement says there is no indication it was shot down. Early signs point to some sort of mechanical problem.
The four crew members and 10 soldiers on board were assigned to Task Force Lightning.
Because of ambushes and roadside bombs, the military relies heavily on helicopters to move troops around. But dozens of choppers have crashed, either from accidents or hostile fire.
The latest crash is the worst since January 2005. That's when a Sea Stallion transport went down in a sandstorm in western Iraq, killing 31 Americans.
At least 3,721 Americans have died in Iraq since the war began.