China's Ministry of Environmental Protection Wednesday urged local government agencies to step up checks on heavy metals industries and punish those companies illegally discharging pollutants.

Tao Detian, a spokesperson with the ministry, made the remarks at a press conference in Beijing, while issuing a list of 19 companies penalized for causing heavy metals pollution.

The list came as a result of nationwide inspections by the ministry on companies with heavy metals emissions.

Tao said the listed companies, besides being fined for causing pollution, had to improve their waste disposal systems to meet environment standards within a specified period.

Eight stibium smelting companies in the tin ore mine area of Lengshuijiang City, Hunan Province, were found causing excessive sulfur dioxide emissions, said Tao.

Eight other companies from different provinces were involved in environmental protection rules violations, excessive waste emissions or inappropriate disposal of dangerous waste.

Another three in Nandan County, south China's Guangxi Zhuang Autonomous Region, were listed for having no comprehensive system to collect liquid waste.

Nandan County Yutai Ore-dressing Plant had been ordered to close by local authorities, while Nandan Nanfang Non-ferrous Metals Smelting Co., Ltd., and Nandan County Jinfa Smelting Plant would be closed if unable to promptly meet environmental standards.

According to the ministry, last year 2,183 heavy metals companies were penalized for illegal operations and 231 were closed.