GUIYANG - Four people were killed and more than 30 injured in a pileup involving 12 vehicles in southwest China's Guizhou Province on Tuesday morning, local authorities said.

Six trucks, four cars, a bus and a minivan ran into each other following a collision in heavy fog at about 8 a.m. on a highway in Jianhe County of the Qiandongnan Miao and Dong Autonomous Prefecture, according to the prefecture fire department.

Firefighters are still clearing the road.

An investigation is underway.

The mangled wreckage of a car at the scene of a 12-vehicle pileup that killed at least four people and injuring more than 30, in Southwest China's Guizhou province, on Dec 3, 2013. [Photo by Wu Ruxiong/Asianewsphoto]