In a statement, officials said all aboard were military personnel, and "all were killed."
The military did not identify the type of helicopter or what caused the crash. The Blackhawk helicopter is widely used in Iraq by U.S. forces, and can carry around 10 passengers and four crew.
Dozens of helicopters have crashed in Iraq since the 2003 U.S. -led invasion of the country. Several of them were shot down by insurgents.
(compiled from agency reports)