The U.S. military continued to fly tilt-rotor Osprey aircraft in Japan on Friday, despite Tokyo's request to suspend the operations in the wake of a crash two days earlier near the southwestern island of Yakushima.

Foreign Minister Yoko Kamikawa said earlier in the day that Japan has been informed by the U.S. Embassy in Tokyo that Washington recognizes a formal request from its Asian ally to ground the aircraft.

An Osprey aircraft takes off from U.S. Marine Corps Air Station Futenma in Ginowan, Okinawa Prefecture, on Dec. 1, 2023. (Kyodo)
File photo taken in September 2018 shows a CV-22 Osprey aircraft at the U.S. military's Yokota Air Base in the western suburbs of Tokyo. (Kyodo) 

The crash Wednesday afternoon of the U.S. Air Force's CV-22 aircraft killed a crew member, marking the first-ever fatality in Japan in a crash involving an Osprey. Seven others remain missing, prompting Japan to ask the United States to ground its Ospreys until it ensures they are safe to fly.

The Japanese Defense Ministry said, however, there were 20 flights by U.S. MV-22 Ospreys, the variant used by the U.S. Marine Corps, from bases in the southern island prefecture of Okinawa from Thursday morning until 3:30 p.m. the same day, according to the minister.

Kyodo News can confirm that an Osprey took off at around 11:30 a.m. on Friday from the U.S. Marine Corps Air Station Futenma in Okinawa, which hosts the bulk of U.S. military facilities in Japan.

Chief Cabinet Secretary Hirokazu Matsuno expressed concerns Friday that "flights are being carried out without sufficient explanation about safety, despite repeated requests from Japan."

In Washington on Thursday, U.S. Defense Department spokeswoman Sabrina Singh said that the military is continuing to operate its Osprey aircraft in Japan and that she was not aware that the Pentagon has received a formal request from Japan to halt Osprey flights.

Her remarks came after the defense and foreign ministers of Japan said Thursday they had asked the United States to ground its Ospreys, indicating a lack of effective communication on the issue between Tokyo and Washington.

Singh also stressed during a press briefing the Pentagon's immediate focus is to search for the missing people and investigate the cause of the incident.

"We have a commitment to safety. There is an investigation that is currently determining and looking into what exactly happened with this aircraft," she said.

"Should that investigation yield (any) results that require the department to change anything about the Osprey or to take additional steps, we will certainly do that," she added.

In Tokyo, Matsuno, the top government spokesman, emphasized Friday that Japan has "officially" called on Washington not to conduct Osprey flights except for search and rescue operations.

It is "deeply regrettable" as the Osprey accident has caused "great anxiety to people," Matsuno said at a regular press conference, urging the United States to provide more information about the safety of the aircraft.

Japanese Defense Minister Minoru Kihara said at a separate news conference the same day, "I do not think there is enough information yet" from the United States about the crash.

The U.S. Air Force tilt-rotor aircraft, based out of Yokota Air Base in the western suburbs of Tokyo, disappeared from radar at around 2:40 p.m. on Wednesday off the island of Yakushima in Kagoshima Prefecture and crashed into nearby waters.

Members of Japan's Ground Self-Defense Force search the coast on the island of Yakushima, Kagoshima Prefecture, on Dec. 1, 2023, following the crash of a U.S. military CV-22 Osprey aircraft in nearby waters two days earlier. (Kyodo)

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