The work safety watch dog in southwest China's Guizhou Province said on Monday that it shut down 735 non-coal mines that did not meet safety standards in 2011, in an effort to boost safety supervision in the resource-rich region.

The provincial work safety bureau has launched overhauls to ensure safety at mines. Officials have been punished after accidents occurred in illegally operated mines under their watch, said Li Shangkuan, head of the bureau.

However, the bureau did not give breakdowns of the mines forced into closure. Non-coal mines include those that are producing any other material that isn't coal. Guizhou has rich reserves of barite, phosphorite, alumina and mercury.

Li said that, in 2011, the bureau also raised the threshold for companies to enter the non-coal sector.

Li said the provincial authorities will continue efforts to regulate mines and push for mining companies to merge in the name of safety, as small mines are generally less safe than big ones.