PHITSANULOK, Thailand – Five military personnel were injured Wednesday when a helicopter made a hard landing north of the central city of Phitsanulok during the Cobra Gold exercise.

The injured were transported to medical facilities for treatment, said U.S. Air Force Capt. Cody Chiles, a spokesman for Cobra Gold 2013. Neither the names nor nationalities of the injured were immediately released.

Cobra Gold is a multinational exercise, but most of the participants are U.S. soldiers and Marines and Thai troops. It is scheduled to conclude Thursday.

The CH-46E Sea Knight helicopter, with the Marine Medium Helicopter Squadron 262, 31st Marine Expeditionary Unit, made the hard landing around noon.

The incident is being investigated, Chiles said.

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