Residents spend their leisure time in an air-raid shelter at People's Square in Chongqing, southwest China, July 11, 2018. An orange alert for high temperature was issued by the local observatory on Tuesday. The air-raid shelters, once used to protect Chongqing residents from air attacks during war time, have turned out to be an ideal place to escape from the scorching heat. (Xinhua/Wang Quanchao)

Children play in an air-raid shelter at People's Square in Chongqing, southwest China, July 11, 2018. An orange alert for high temperature was issued by the local observatory on Tuesday. The air-raid shelters, once used to protect Chongqing residents from air attacks during war time, have turned out to be an ideal place to escape from the scorching heat. (Xinhua/Wang Quanchao)