A brief statement said Colonel Mark S. Coppess had been relieved of duty as commanding officer of the Futenma base "due to a loss of trust and confidence in his ability to lead his command."

There was no immediate comment or further detail from the Marines on why Coppess had been dismissed, but a US defence official told AFP it had nothing to do with a string of accidents that have plagued military aircraft in Japan.

In February, the commander of the Marines' Japan-based Osprey squadron was fired after several accidents involving the hybrid aircraft.

The most serious, in 2017, involved the crash of an MV-22 Osprey off the east coast of Australia.

The issues involving US military aircraft in Japan have stoked tension over the US military presence in the country.

Okinawa hosts the bulk of some 47,000 US troops based in Japan, and their presence has been a source of friction with residents.

The prefecture was the site of a major World War II battle that was followed by a 27-year US occupation of the island, and it would serve as a launchpad for any American military activity in Asia.