The Chinese sailors man the rails aboard the hospital ship Peace Ark as the ship leaves a military port in Sanya in south China's Hainan Province on September 12, 2015. A Chinese naval taskforce, composed of the guided-missile destroyer Lanzhou, the guide-missile frigate Yueyang and the hospital ship Peace Ark, left a military port in Sanya in south China's Hainan Province on September 12 for a military exercise jointly held by China and Malaysia. The joint military exercise, codenamed "Peace and Friendship 2015," is scheduled to be held from September 17 to 22 in the Malacca Strait and its adjacent area.