SpaceWar.com reports: “Japan voiced ‘strong concern and protest’ Saturday after a Chinese naval ship entered its territorial waters, days after Tokyo accused Beijing of sending a military aircraft into Japanese airspace.

A Chinese naval vessel was spotted entering Japanese territorial waters near the southern Kuchinoerabu island at around 6:00 am Saturday (2100 GMT Friday) and exiting southwest of Yakushima island nearly two hours later, the defence ministry said.

Following the incident, the foreign ministry ‘issued Japan’s strong concern and protest’ to China’s embassy in Tokyo.

The ministry took ‘into account the past activities of Chinese naval vessels and others in the waters around Japan, and the recent intrusion into Japan’s territorial airspace by a Chinese military plane,’ it said late Saturday.

Japan on Monday scrambled fighter jets after a two-minute incursion by Chinese Y-9 surveillance aircraft off the Danjo Islands in the East China Sea, which Tokyo slammed as a ‘serious violation’ of its sovereignty.

China’s growing economic and military clout in the Asia-Pacific region and its assertiveness in territorial disputes — most recently with the Philippines — has rattled the United States and its allies…”