A surface-to-air missile is fired from a missile launcher by the air force under the PLA Southern Theater Command during a round-the-clock air defense training exercise on November 13, 2019. The surface-to-air missile brigade conducts training on fast direct attacks, field maneuver, air-to-ground engagement, live-fire operation and other subjects. (eng.chinamil.com.cn/Photo by Zhang Hengping and Yuan Hai)

A surface-to-air missile is fired from a missile launcher by the air force under the PLA Southern Theater Command during a round-the-clock air defense training exercise on November 13, 2019. The surface-to-air missile brigade conducts training on fast direct attacks, field maneuver, air-to-ground engagement, live-fire operation and other subjects. (eng.chinamil.com.cn/Photo by Zhang Hengping and Yuan Hai)