The chopper, part of the 1st Marine Expeditionary Brigade, on Wednesday made "what is best described as a 'hard landing,' then rolled and subsequently caught fire," US Central Command said.

"The crew escaped without injury and was successfully rescued by another helicopter operating in the area," it said.

"Hostile fire is not a cause," said the statement, adding that the crash was under investigation.

The CH-53, nicknamed the "Super Stallion," is designed for the transport of heavy material and supplies and is able to refuel in the air.

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