Workers tested the river October 31 after a high number of dead fish turned up, the ministry said. Laboratory testing found high cyanide levels in some fish.
The cyanide accidentally spilled into the river from the Hambledon Mining Plc gold-processing plant October 29, Novosti-Kazakhstan reported November 2.
Authorities closed down local schools and are delivering water to the affected area, RFE/RL reported. They plan to finish cleaning up the river by November 4, Novosti-Kazakhstan reported.
The British-owned plant has stopped operating and will be back to work November 7. Source