MOSCOW, September 21 (RIA Novosti) -- Russian and Chinese warships have completed a joint anti-piracy exercise which involved escorting a convoy of 23 merchant vessels in the Gulf of Aden, a Pacific Fleet official said on Monday.

The official added that nine of the 23 vessels were sailing under Russian flags.

The three-day exercises, which started on September 18 and included Russia's Admiral Tributs destroyer and two Chinese warships, the Zhoushan and Xuzhou, along with a number of support vessels, were focused on search-and-detain operations.

A new element in these exercises has been the search, location and detention of a dummy pirate vessel.

The Russian warship will now resume regular escorts of commercial vessels through waters off the Somali coast.

The third Russian task force from the Pacific Fleet, led by the Admiral Tributs with two helicopters on board, arrived in the Gulf of Aden on July 30.

The previous two task forces from the Pacific Fleet were led by the Admiral Vinogradov and Admiral Panteleyev destroyers.

The fleet's warships have escorted over 100 Russian and foreign commercial ships and prevented several pirate attacks since January 2009.

The Pacific Fleet will send a fourth task force, comprising a missile destroyer, two support ships and a naval infantry unit, to the Gulf of Aden after the Admiral Tributs finishes its current anti-piracy mission in the region at the end of October.

Around 35 warships from the navies of 16 countries are currently deployed off Somalia's coast to counter frequent pirate attacks on key trade routes.

Pirate attacks on commercial vessels in the Gulf of Aden and off the east coast of Somalia have totaled 148 since the beginning of the year, with over 40 ships captured and at least 270 personnel taken hostage.