HEFEI, Jan. 6 -- Seven people were killed in a highway pileup involving four vehicles in east China's Wuhu City Sunday morning, according to the municipal authorities.

All of the deaths occurred on a mini-bus which piled up with three trucks in the fog on the Shanghai-Chongqing Highway that passes Wuhu.

The collisions happened at around 8:40 a.m. An investigation is still under way.