An unmanned Chinese military aircraft was spotted in the airspace between the main island of Okinawa and Miyakojima island in Okinawa Prefecture, the Defense Ministry announced Monday.
The ministry said the TB-001 drone, which has attack capabilities, then took a flight path over the Pacific Ocean.
It was the first time a Chinese drone flew in the airspace without being escorted by a manned aircraft, the ministry said.
There was no incursion into Japanese airspace.
The aircraft flew from the East China Sea and headed south in the airspace, the ministry said. It then made a circle over the Pacific Ocean south of the Sakishima Islands in the prefecture before heading for the Bashi Strait near southern Taiwan. Air Self-Defense Force fighter jets were scrambled in response.
The ministry is investigating issues such as the purpose of the flight.