TOKYO, Nov. 10 (UPI) -- Japan's Defense Agency suspects that an unidentified submarine sighted in Japanese waters early Wednesday was a Chinese nuclear submarine, Kyodo News reports.
The Japanese government dispatched Marine Self-Defense Forces to secure the area after the sub was seen briefly in waters near a chain of islets in Okinawa. Patrol planes continued to track its movements after the brief intrusion, Chief Cabinet Secretary Hiroyuki Hosoda told reporters.
The marine forces had been tracking the sub since Monday, but refrained from firing warning shots since the sub did not remain long in Japanese waters, Hosoda said.
Japanese forces spotted two Chinese Navy vessels, one to rescue submarines and another to tow ships, operating in waters southeast of Tanegashima Island since Friday, and were investigating a possible relationship to the submarine incident, officers of the marine forces said.
The two Chinese ships had repeatedly changed direction and speed Monday in waters south of the island, but left toward the East China Sea Tuesday, they said, adding that the submarine might have been experiencing trouble.
