Four Chinese coast guard ships entered Japanese waters around the disputed Senkaku Islands in the East China Sea on Wednesday, the Japan Coast Guard said.
The vessels entered the territorial waters shortly after 10 a.m. in the first such incident this year. China Coast Guard ships last entered the waters around the group of uninhabited islets on Dec. 26.
A Japanese coast guard ship demanded that the vessels leave the waters. Beijing claims the Japanese-administered islands, called Diaoyu in China. (PNA/Kyodo)