Four Chinese government ships were spotted on Tuesday in Japan's territorial waters off the Senkaku Islands in the East China Sea.

Japan Coast Guard officials say the vessels entered the waters off Uotsuri Island from shortly after 10:30 a.m. after navigating through the contiguous zone just outside the territorial waters.

The four ships stayed in Japan's waters for 1 hour and 45 minutes.

This is the first time this year that Chinese government ships have been sighted in Japan's territorial waters off the Senkakus.

Japan controls the islands. The Japanese government maintains they are an inherent part of Japan's territory. China and Taiwan claim them.