Lt. Patrick Evans, a spokesman for the U.S. military, said the crash did not appear to be the result of insurgent fire, CNN reported.
The UH-60 Blackhawks were landing at Combat Outpost Ford in northern Baghdad.
Two U.S. and two Iraqi soldiers were hurt, Evans said.
Another U.S. helicopter crashed late Saturday during a gunfight between Iraqi forces and insurgents in a Shiite stronghold in eastern Baghdad, Interior Ministry officials said. The area had been sealed off whiel the fighting continued, and the number of casualties was unknown.
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