Japan's Defense Ministry says a group of Chinese vessels including an aircraft carrier passed between two islands of Okinawa Prefecture on Friday.

The Maritime Self-Defense Force confirmed the carrier Liaoning and accompanying ships sailed from the East China Sea to the Pacific Ocean through waters between Okinawa's main island and Miyakojima island.

It is the first confirmed passage through the area by a Chinese carrier since May.

Ministry officials say the vessels did not enter Japan's territorial waters.

They say two state-of-the-art missile destroyers were among the ships accompanying the carrier.

Officials believe the vessels could stay in the Pacific for a while and conduct a drill.

The defense ministry is analyzing the purpose of the navigation and maintaining close surveillance.