Chinese marine surveillance ship Haijian No. 46 (L) tries to approach towards Japanese fishing boats (2nd and 3rd from front) while a Japan Coast Guard boat sails (front), in the East China Sea, near Diaoyu islands, in this photo taken by Kyodo May 26, 2013. [Photo/Agencies]

BEIJING -- A fleet of four the China Coast Guard (CCG) ships patrolled territorial waters surrounding the Diaoyu Islands, on Saturday, according to a State Oceanic Administration statement.

The fleet, composed of CCG 2350, 1115, 2112 and 2506, conducted a comprehensive patrol in the adjacent waters encompassing the Diaoyu Islands, Huangwei Yu, Beixiao Dao and Nanxiao Dao in two groups, the statement said.

During the patrol, the fleet ordered Japanese ships that had entered China's territorial waters to leave the area immediately in accordance with  Chinese law and regulations.

The CCG, which covers maritime law enforcement functions of four agencies responsible for fisheries administration, maritime surveillance, customs enforcement and border control, formally unveiled its board in July.