Artillerymen assigned to an air-defense brigade under the PLA Xizang Military Command fire a towed howitzer system at mock targets during a recent live-fire training operation at the altitude of 4,500 meters in southwestern China's Xizang Autonomous Region. The brigade conducts such training subjects as long-distance and round-the-clock real combat live-fire training operation, reconnaissance, electronic interference operation, and so on, in order to test troops’ air-defense capabilities. (eng.chinamil.com.cn/Photo by Wang Haotian)