US military helicopter crashes inside Okinawa base

A US military helicopter crash-landed inside the training area at Okinawa's Camp Hansen on Monday with four crew members inside, raising a plume of smoke that local civilians could see from a hillside.

Three out of the four crew members appear to have survived the crash, said Japanese Defense Minister Itsunori Onodera, wrote the Associated Press, while a fourth member remains missing.

The cause of the crash remains unknown, and no casualties were reported among area residents. 

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The aircraft involved in the incident appears to be a HH-60 rescue helicopter belonging to Kadena Air Base, wrote Stars and Stripes.com, while others have reported that the aircraft was a CH-46 helicopter instead. It was on an unspecified training mission when it crashed.

Residents of Okinawa, already displeased with the heavy US military presence in their area, may take this latest incident as more evidence to support their efforts to relocate the thousands of troops stationed there elsewhere. 

Recently, Okinawans have publicly protested a shipment of 12 MV-22 Osprey transport air craft to the Okinawa air base. 

In April, the US agreed to return some land located by the Kadena Air Base to the Japanese, which will entail returning some of the troops stationed there back to the US, or to other places.