TOKYO — One of two Marines, rescued after a pair of warplanes collided in midair, has died, military officials said Thursday as rescue crews continued to search for five still missing.

The crash happened while their crafts were refueling some 200 miles off Japan, U.S. and Japanese authorities said.

The planes, a KC-130 refueling aircraft carrying five crew members and an F/A-18 fighter jet carrying two, "came in contact" and crashed into the sea at around 1:42 a.m. Thursday (11:42 a.m. ET Wednesday), said Yoshihide Suga, Japan's chief cabinet secretary.

The Japanese Defense Ministry initially said that two of the seven Marines had been rescued. But one of those two has since died, Marine spokesman Capt. Chris Harrison said.

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The aircraft had launched from Marine Corps Air Station Iwakuni, Japan, on a regularly scheduled training exercise, the Marines said. Suga said the Defense Ministry had asked the U.S. for more information.

UPDATE:



One of the personnel involved in the mishap is being evaluated by competent medical authorities at @MCASIwakuni. The search and rescue operations continue for the remaining six Marines. — U.S. Marines (@USMC) December 6, 2018

The crash is the latest in a recent series of accidents involving the U.S. military deployed to and near Japan.

Last month, a U.S. Navy F/A-18 Hornet from the aircraft carrier USS Ronald Reagan crashed into the sea southwest of Japan's southern island of Okinawa, though its two pilots were rescued safely. In mid-October, a MH-60 Seahawk also belonging to the Ronald Reagan crashed off the Philippine Sea shortly after takeoff, causing non-fatal injuries to a dozen sailors.

More than 50,000 U.S. troops are based in Japan under the bilateral security pact.

U.S. Ambassador to Japan William Hagerty paid his respects to those injured and missing and thanked Japan for its help.

"I am encouraged by the fact that the United States and Japan have worked so closely together, and I would like to thank Japan's Self Defence Force for immediately joining us in a closely integrated exercise to search and rescue for those involved," he said.

He went on to underline the two country's ties, and the role American forces play in keeping the region safe.

Marines "risk their lives every day to protect Japan and to protect this region, and sometimes they pay the greatest cost," he said. "I want to emphasize this security alliance that we have is critical and it is moving forward in a very positive direction."

Arata Yamamoto reported from Tokyo; Alex Johnson from Los Angeles; Doha Madani from New York; Hans Nichols and Mosheh Gains from Washington.