SHANGHAI, May 23 -- The Chinese and Russian navies staged exercises on the East China Sea on Friday to simulate anti-piracy operations.

In the "joint escort" drill, naval vessels successfully drove away two "pirate boats" under the command of Russia's Varyag missile cruiser. The navies also simulated a rescue mission by sending out special forces and taking out "pirates" on a "hijacked ship."

In a joint aircraft identification exercise, vessels searched for and reported "unidentified aerial targets" while the command coordinated flying J-10 and Su-30 fighters to identify the targets.

The navies also jointly conducted air defense and maritime assault drills. They also practised intercepting missiles.

Wang Chao, head of a coordination team from the Chinese Navy, described Friday as "the busiest day" since the week-long series of drills began on Tuesday, with the exercises lasting from about 9 a.m. till 3:30 p.m.