QINGDAO, Oct 3 (Xinhua) -- A Chinese naval flotilla returned to a military port in Qingdao in East China's Shandong province Tuesday after a joint military exercise with the Russian navy.

The joint drill, held from Sept 18 to 25 in the Sea of Japan and Okhotsk, was the second phase of "Joint Sea 2017." The first stage was held in the Baltic Sea in July.

The flotilla consisted of missile destroyer Shijiazhuang, missile frigate Daqing, comprehensive supply ship Dongpinghu, and submarine rescue ship Changdao.

During the week-long drill, naval forces from both sides conducted a string of joint operations, including air defense, anti-submarine and anti-fleet actions as well as maritime rescues.

It was the first time the two sides have conducted joint submarine rescue exercises and joint anti-submarine drills involving multiple arms of service and types of aircraft and ships.

The drill has consolidated and advanced the Sino-Russian comprehensive strategic partnership of coordination, deepened friendly and practical cooperation between the two militaries, and improved abilities to jointly cope with security threats at sea, according to military sources.