A Chinese vessel spotted in waters near the Japan-administered Senkaku Islands last week was a nuclear-powered attack submarine, Defense Minister Itsunori Onodera said Monday.
The Shang-class submarine was detected Thursday while submerged just outside Japanese territorial waters near the Senkaku Islands in the East China Sea. On Friday, it was seen in the high seas, cruising with a Chinese flag. Tokyo filed a protest with Beijing, saying the sub’s presence raised bilateral tensions.
“We are seriously concerned over acts that unilaterally raise tensions. We’ll keep our guard up to respond swiftly if a similar incident happens,” Onodera told reporters, noting that the Shang-class vessel is capable of launching long-range cruise missiles.
A Defense Ministry source speculated that China may have deployed the sub to test the Maritime Self-Defense Force’s patrolling capabilities.
The sovereignty of the Senkaku Islands, claimed as Diaoyu by Beijing and Tiaoyutai by Taiwan, is a perennial thorn in relations between Asia’s two largest economies, which otherwise have been showing signs of improving.
The development has alarmed Japan as it was the first time a Chinese submarine has been found in the so-called contiguous zone around the uninhabited islets. The contiguous zone is a band of water beyond the 12 nautical mile territorial waters surrounding any national territory, and extends out to 24 nautical miles.
Also on Monday, three China Coast Guard ships entered Japanese territorial waters off the Senkakus in Okinawa, China’s second intrusion this year since Jan. 7.
According to the Japan Coast Guard’s 11th regional headquarters in Okinawa’s capital Naha, the Haijing 2303, Haijing 2308 and Haijing 2401 crossed into Japanese waters at a point north-northwest of Uotsuri — the largest islet in the disputed chain — roughly between 10:15 a.m. and 10:25 a.m.
The three Chinese ships left the area at a point west-southwest of Uotsuri roughly between 11:45 a.m. and noon.
At a Monday news conference in Tokyo, Chief Cabinet Secretary Yoshihide Suga called the intrusion “extremely regrettable,” saying the islands are “Japan’s inherent territory legally and historically.”
Suga indicated the government intended to speed up work with China to launch a proposed bilateral air and maritime communication mechanism aimed at preventing accidental clashes between the two nations in or above the East China Sea.