Tons of dead fish are rotting in the Piracicaba River in Sao Paulo state downstream from where local authorities say a sugar and ethanol plant dumped industrial waste this month.Public prosecutors said ongoing investigations by state environmental agency Cetesb made a conservative estimate of as many as 20 tonnes of dead fish in the river about 200 km (125 miles) northwest of the state capital.

An estimated 10 to 20 tons of fish died on the Piracicaba River, prosecutors said. An initial investigation points to an "irregular discharge of wastewater" from a sugar and ethanol plant.

Several tons of fish have died along one of the main rivers in Brazil’s Sao Paulo state after an alleged illegal dumping of industrial waste from a sugar and ethanol plant

The initial investigation points to an "irregular discharge of wastewater" from a sugar and ethanol plant that reached a stream that flows into one of the main rivers in Sao Paulo.