DUBAI, United Arab Emirates: The U.S. Navy says one of its helicopters has crashed in the Gulf nation of Oman with five crew members aboard.

Lt. Greg Raelson, a spokesman for the Navy's Bahrain-based 5th Fleet, gave no immediate word on the fate of the crew Thursday. But an Omani air force official says three of them have been found so far and are being treated in a hospital. The official was not authorized to release the information and spoke on condition of anonymity

No hostile activity is suspected.

Raelson says an investigation is under way into crash of the MH-35E Sea Dragon. He says the helicopter was assigned to a mine countermeasure squadron and was involved in heavy lift operations when it crashed 58 miles (93 kilometers) southwest of the capital Muscat.