Chinese and Japanese coast guard ships faced each other in the waters surrounding the disputed islands in the East China Sea on Wednesday, with both countries announcing the deployment of patrol vessels to urge the other party to leave the area. The Chinese coast guard claimed that three Japanese ships and several patrol vessels unlawfully entered Chinese territorial waters on Wednesday, and that necessary control measures were taken according to the law. Meanwhile, the Japanese coast guard indicated that its patrol ships repeatedly urged three Chinese coast guard vessels to leave the waters. A similar incident occurred on October 17. Both China and Japan assert sovereignty over the disputed islands, referred to by China as the Diaoyu Islands and by Japan as the Senkaku Islands.