TOKYO (AP) – Japan has detected an allegedly Chinese submarine off an island in southern Japan, the Defense Ministry said on Sunday, stepping up Japan’s cautious levels in the East China Sea then that China increases its military activities.
The submarine remained submerged, but the ministry said in a statement that it believed the submarine was Chinese because a Chinese Luyang III-class guided missile destroyer was near the submarine.
The submarine moved northwest of the east coast of Amamioshima Island, about 700 kilometers (420 miles) northeast of the disputed East China Sea islands controlled by Japan but also claimed by Beijing, the ministry said.
On Sunday morning, the submarine was heading west into the East China Sea.
Neither the submarine nor the ship entered Japanese territorial waters. Under international law, submarines passing off the coast of another country must surface and display a national flag within territorial waters.
The Japan Maritime Self-Defense Force has sent three reconnaissance planes and two destroyers to the region for early warning and intelligence gathering to analyze China’s intentions.
A submarine believed to be Chinese was also spotted in the region in June 2020.
China has defended its maritime activities and claims to have the right to defend its sovereignty, security and development interests.
Japan, alarmed by China’s growing naval activity in the East and South China Seas, has stepped up its defense in the southwestern regions of the country and the islands north of the disputed islands.
Tokyo says it opposes unilateral attempts by China to change the status quo in the region and regularly protests against the growing presence of the Chinese coastguard near the disputed islands. Japanese authorities say Chinese ships routinely violate Japanese territorial waters around the islands, sometimes threatening fishing vessels.