Vehicles move as they are engulfed by a hazy day in Jinan, capital of east China's Shandong Province, Feb. 28, 2013. Pollution worsened in China's north and east provinces as a sand storm hit the region on Thursday. (Xinhua/Guo Xulei)
Residential buildings are seen engulfed by a hazy day in Jinan, capital of east China's Shandong Province, Feb. 28, 2013. Pollution worsened in China's north and east provinces as a sand storm hit the region on Thursday. (Xinhua/Guo Xulei)
A women wearing a facemask walks in a hazy day in Jinan, capital of east China's Shandong Province, Feb. 28, 2013. Pollution worsened in China's north and east provinces as a sand storm hit the region on Thursday. (Xinhua/Guo Xulei)
A man walks on a walking path in Taiyuan, capital of north China's Shanxi Province, Feb. 28, 2013. Pollution worsened in China's north and east provinces as a sand storm hit the region on Thursday. (Xinhua/Zhan Yan)
A woman rides a bicycle in a hazy day in Taiyuan, capital of north China's Shanxi Province, Feb. 28, 2013. Pollution worsened in China's north and east provinces as a sand storm hit the region on Thursday. (Xinhua/Zhan Yan)
A woman covers her nose and mouth as she walks in a hazy day in Taiyuan, capital of north China's Shanxi Province, Feb. 28, 2013. Pollution worsened in China's north and east provinces as a sand storm hit the region on Thursday. (Xinhua/Zhan Yan)