Heavy smog hit Sihong in east China's Jiangsu Province on Dec. 4. The National Meteorological Center on Wednesday renewed a yellow alert for fog and smog for the third consecutive day as smog continued to choke eastern and northern provinces and municipalities, including Shandong, Jiangsu, Zhejiang, Shanghai and Tianjin. School classes will be suspended, government vehicles will be removed from roads and barbecue grills will be banned in Nanjing and Qingdao where lingering smog has led to soaring pollution levels. [Photo/Chinanews.com]