Engineers work on a collapsed viaduct in Mianchi County, Sanmenxia City, central China's Henan Province, Feb. 3, 2013. A part of the expressway viaduct collapsed on Friday morning when an explosion caused by a truck loaded with fireworks took place. Ten people died and 11 others were injured in the accident. Local transportation authority conducted a safety evaluation on the viaduct with vehicle restrictions. [Xinhua]