Several sources close the government disclosed on July 30 that a Chinese naval frigate that entered Japan’s contiguous zone off the Senkaku Islands in Okinawa Prefecture on July 4 continued to stay in the waters around the islets for about a week. Chinese warships have sailed through the waters near the Senkakus in the past, but it is unusual for such a ship to stay there longer. Japan has already conveyed to China through diplomatic channels that it is “closely monitoring” the situation, raising alarm that China may move to step up its territorial claim over the Senkakus.

According to the Ministry of Defense, the frigate later left the waters near the Senkakus to sail toward the Pacific Ocean between Yonaguni Island and Taiwan on July 7. It returned the East China Sea after sailing back between Yonaguni and Taiwan on July 10. (Abridged)