Chinese peacekeepers, who were injured in a terrorist attack in Mali last month, are greeted after returning to Beijing, capital of China, June 27, 2016. Four injured Chinese peacekeepers, with two in serious conditions, returned to Beijing on Monday. Chinese UN peacekeeping soldier Shen Liangliang, 29, was killed in the terrorist attack on the night of May 31 in the northern Malian town of Gao, when a vehicle-borne improvised explosive device was detonated at a United Nations camp. (Xinhua/Zhang Lupeng)

Injured Chinese peacekeeper Si Chongchang (L) waves to people as he leaves a hospital in Dakar, Senegal, on June 26, 2016. Four Chinese peacekeepers, injured in terrorist attacks in Mali, left for China on Sunday. (Xinhua/Wang Meng)

Injured Chinese peacekeeper Li Tao (C) is carried onto an ambulance to leave a hospital in Dakar, Senegal, on June 26, 2016. Four Chinese peacekeepers, injured in terrorist attacks in Mali, left for China on Sunday. (Xinhua/Wang Meng)