China is holding military exercises in the East China Sea amid rising tensions with Japan over each country's claim to a chain of uninhabited islands.
The official Xinhua news agency said the October 19 exercise involves 11 vessels from the East China Sea fleet and eight aircraft.
Xinhua says patrol vessels from the fishery administration and the marine surveillance agency have been stalked and harassed by foreign vessels while carrying out missions.
On October 16, Japanese military aircraft spotted seven Chinese warships not far from the disputed islands, called Diaoyu in Chinese and Senkaku in Japanese.
China said the ships were on a routine training mission.
Based on reporting by AP and dpa