Sandstorms sweep through northern China

People wearing masks walk in Tianjin, north China, May 4, 2017. Since Wednesday, the country's northern areas have witnessed severe sandstorms, affecting more than 10 provincial-level regions and covering an area of 1.63 million square kilometers. The sandstorms have resulted in serious air pollution and the national weather observatory issued an alert on Thursday in response to the sandstorm, which was forecasted to linger into Saturday. (Xinhua/Yue Yuewei)