The exercises occurred as China raised vociferous objections to Japan purchasing the Daioyu/Senkaku islands in the East China Sea from a private party.
China claims the islands were part of it from ancient times and Japan appropriated them after the Second World War.
China has also dispatched two maritime surveillance ships to the islands after announcing that the region formed part of the baseline of its maritime boundary.
The exercises were also reported to be a retaliation to recent Japan-United States military exercises which involved mock takeover of islands.
Separately, state run Xinhua news agency reported that China will conduct routine patrols near the Diaoyu Islands to assert the country's sovereignty and protect fishermen.
Data showed that over 1,000 Chinese fishing boats enter the waters of the Diaoyu Islands each year, with their total catch exceeding 150,000 tonnes, it quoted an official of the ministry of agriculture as saying.
However, increasing "harassment" from Japanese ships in recent years has severely affected China's fishing activities, triggering widespread protest and condemnation of Japan, the report said.
In order to safeguard the interests of China's oceanic fishing industry and ensure safety for its fishermen, the ministry has asked fishery authorities in Zhejiang and Fujian provinces to include areas surrounding the Diaoyu Islands in their regular patrol scopes, the official was quoted as saying.