The Chinese vessels entered the area near the Japanese-controlled Senkaku Islands at 10:40 am (0140 GMT) and sailed there for one and a half hours, the Japan Coast Guard said.
The Senkaku Islands are also claimed by China and Taiwan, where they are called Diaoyu and Tiaoyutai respectively.
On Sunday, China's first aircraft carrier was also spotted in the region and near Taiwan, Tokyo said.
The aircraft carrier Liaoning was part of a fleet that was seen sailing in the East China Sea, 110 kilometres north-east of the Japanese island of Miyako, Chief Cabinet Secretary Yoshihide Suga told a news conference Monday.
The move indicated "enhancement of the capabilities of China's naval power," Suga said.
Beijing said Saturday the Liaoning was headed for the western Pacific to join an open-sea training exercise.
Published : December 26, 2016
By : Deutsche Presse Agentur