WASHINGTON: One US Marine was killed and rescue teams were searching for five others who were missing after two Marine Corps aircraft collided in mid-air and crashed into the sea off the coast of Japan, officials said on Thursday.

Earlier, Japanese and American officials said they had so far found two of the seven Marines who had been aboard the aircraft, an F/A-18 Hornet fighter jet and a KC-130 Hercules.

“One of the recovered Marines is in fair condition and the other has been declared deceased by competent medical personnel,” a US Marine Corps statement said on Thursday morning.

Search and rescue operations continue for the remaining five US Marines.

“The aircraft were conducting routine training and aerial refueling was a part of the training,” the US Marine Corps statement said.

The incident occurred around 2 a.m. local time in Japan (1700 GMT Wednesday) about 320 km (200 miles) off the Japanese coast.

The incident adds to a growing list of US military aviation accidents around the world in recent years, prompting hearings in Congress to address the rise.

US military accidents are a sensitive topic in Japan, particularly for residents of the southern prefecture of Okinawa, home to the bulk of the US presence in the country. A series of emergency landings and parts falling from US military aircraft have highlighted safety concerns.

People in a Tokyo hospital waiting room fell silent as news of the crash came on television, with one woman whispering to another, “This is so scary.”

“The incident is regrettable, but our focus at the moment is on search and rescue,” Japanese Defense Minister Takeshi Iwaya told a news conference. “Japan will respond appropriately once the details of the incident are uncovered.