Thirty-eight people have been held accountable for a chemical leak that contaminated a river in North China's Shanxi province in December, a working group responsible for addressing the incident said Wednesday.

An investigation by the working group showed that Tianji Coal Chemical Industry Group caused the serious contamination and the Changzhi city government should also be blamed for failing to respond quickly to the emergency and not informing the downstream areas of the imminent health threats.

Changzhi Mayor Zhang Bao was removed from his post. The director of the work safety department in the city, Yang Fujin, was also sacked. Seven other officials were disciplined, including a deputy mayor and the environmental protection chief in the city. Twenty-four corporate executives received warnings, or demotion and removal from their posts.