Chilean state-owned copper miner Codelco stopped operations of three out of four furnaces at its Ventanas foundry on Sept. 3 after sensing high levels of sulfur dioxide, Reuters reported the same day.

According to the report, the company said that the levels of the gas rose to 20% over the accepted limit for five minutes, due to which it shut down the furnaces as a "voluntary and preventative measure."

The government blamed the state-run energy company, ENAP, for the incident, but the company denied the accusation and said there had been no violation of environmental regulations. Moreover, no injury or illness were reported.

The company, which previously paid fines for emissions in the area, said that the incident would only cause a minor effect on its production.