Twenty-five people were punished after being implicated in the illegal disposal of hazardous chemicals that killed four in Shandong province, the Ministry of Environmental Protection said on Monday. In October, Zhang Linde and Chen Jixin hired a tanker to transport liquid chemical waste to an abandoned coal mine in Zhangqiu, which they had leased to store the chemicals illegally, according to the ministry's report. Zhang, Chen and the tanker driver died of poisoning as a result of exposure to the chemicals. Twenty-five suspects have been dealt with under criminal procedures. Several others remain at large, the report said.