Defense Minister Itsunori Onodera said Monday the government has identified the country whose submarine was detected while submerged the previous day near Okinawa and will call for such encroachments to cease.
Onodera did not disclose the country, saying the vessel did not intrude into Japanese territorial waters, but a government source said Sunday the sub apparently belongs to China.
“We will convey to them that we are fully aware (of the sub’s identification) and urge restraint,” he said. “We need to share information among Japan, the United States and South Korea.”
The unidentified sub was detected by a P-3C patrol aircraft of the Maritime Self-Defense Force early Sunday in Japan’s contiguous zone south of Okinawa’s Minamidaito Island, but it did not enter Japanese waters, the Defense Ministry said.
Sailing in Japan’s contiguous zone, an area outside territorial waters where Japanese law may be applied, poses no problem in terms of international law. But when passing through territorial waters of other countries, submarines must sail on the surface and show their national flags.
The incident came after a suspected Chinese Navy sub sailed submerged in the contiguous zone around Amami-Oshima Island in Kagoshima Prefecture on May 2 and another, also believed to be Chinese, did likewise in the contiguous zone around Okinawa’s Kumejima on May 12.