Fog enveloped a section of expressway in Fuyang City in east China's Anhui Province this morning.
Over 30 vehicles collided due to low visibility on the expressway, leaving 18 people dead and 19 injured, the state- run Xinhua news agency reported.
The injured were being treated in hospital, where the condition of nine is said to be serious.
Several vehicles caught fire due to the accident which caused about three-to-four kilometre long traffic congestion on the highway.
The accident spot was left with twisted and burnt-out wreckage.