WASHINGTON  -   At least one US Marine died in the crash of a KC-130 Hercules and F/A-18 Hornet off the coast of Japan, the III Marine Expeditionary Force announced in a press release on Thursday.

“The United States Marine Corps confirms that two Marines have been found. One is in fair condition and the other has been declared deceased by competent medical personnel,” the release said.

Five other Marines are still missing, and the US 7th Fleet is conducting search and rescue operations along with Navy aircraft out of Kadena Air Force Base and the Japanese Maritime Self-Defense Force and Japanese Coast Guard, the release said.

Two aircraft were involved in a routine training and aerial refueling mission when the crash occurred, but the cause remains under investigation, the release added.