A U.S.-led coalition helicopter crashed Sunday in southeastern Afghanistan after reporting engine failure, officials said, but they declined to give the number of people on board.

"It was not enemy-fire related," said Col. Tom Collins, spokesman for NATO's International Security Assistance Force. "The pilot was able to radio in that he was having engine problems. We're confident it was not due to enemy action."

The coalition has launched a search and rescue operation for the helicopter and its occupants, said U.S. military spokesman Lt. Col. David Accetta.

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"For the safety of the people on board, we will not release the number of people on board until rescue operations are complete," Accetta said. "Rescue operations are under way."

Accetta also declined to give details about the model of the helicopter and the location of the crash.

Zabul provincial governor Dilber Jan Arman said the helicopter fell in the Hassan Kariez area of Shahjoi district. He did not have any information about the number of casualties.

Arman said it was possible that the "helicopter crash was due to bad weather."

The mountainous region of southeastern Afghanistan is under the command of U.S.-led forces.

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