The Japanese Ministry of Defense confirmed that a Russian Navy Vishnya-class intelligence collection ship entered the contiguous zones around Yonaguni Island and Miyako Island between January 13 and January 15 before sailing into the Pacific Ocean.
According to the Joint Staff Office, the vessel—hull number 535—was detected moving northeast through the Yonaguni Island contiguous zone and later transiting waters that included the contiguous zone of Miyako Island. The ministry said the Maritime Self-Defense Force (MSDF) conducted continuous monitoring throughout the ship’s passage.
The Joint Staff Office stated that surveillance was carried out by the MSDF destroyer Ikazuchi of the 1st Escort Division, along with P-1 maritime patrol aircraft from the 1st Air Patrol Squadron and P-3C aircraft from the 5th Air Patrol Squadron, the statement said.
The Vishnya-class is a Russian naval intelligence platform designed to collect communications and electronic signals. Ships in this class are equipped with multiple antenna arrays, radomes, and specialized electronic systems that support long-duration collection operations in contested or sensitive waters.
The Japanese ministry has documented repeated Russian and Chinese naval transits through key waterways surrounding Okinawa and the southwestern island chain. These areas include the Miyako Strait and the waters around Yonaguni Island, both of which are strategically important routes connecting the East China Sea and the western Pacific.
In previous statements, the Ministry of Defense has emphasized that maritime and air assets assigned to southwestern defense sectors remain on steady alert, responding to developments involving foreign naval movements near Japanese territory. The latest detection underscores the sustained presence of foreign military vessels in waters surrounding Japan’s outer islands.
The passage occurred as regional tensions remain elevated, with Japan increasing investment in maritime domain awareness, electronic intelligence, and island-based defense capabilities across the Nansei archipelago. Tokyo has also expanded patrol coverage to monitor growing activity by foreign forces around Japan’s southwestern approaches.
