The vice mayor and environment chief for China's Jilin city, accused of involvement in last month's cover-up of a huge toxic spill, has been found dead, AFP reported. No cause of death was given. The death of 43 year-old Wang Wei came as Beijing warned of severe punishments for those responsible for the cover up. The accident, caused by an explosion November 13 at a nearby petrochemical plant, resulted in 100 tonnes of carcinogenic benzene and nitrobenzene pouring into the Songhua River. China may build an emergency dam to stop the toxic spill from contaminating other rivers as it flows downstream towards the Russian border, state media reported.