A pedestrian walks on street in Shijiazhuang, capital of north China's Hebei Province, Oct. 19, 2016. A yellow alert for air pollution was issued on Wednesday in Hebei Province. (Xinhua/Wang Xiao)
A pedestrian walks on street in Shijiazhuang, capital of north China's Hebei Province, Oct. 19, 2016. A yellow alert for air pollution was issued on Wednesday in Hebei Province. (Xinhua/Wang Xiao)