Dead fish has been found in the Mechetka river in Russia's Rostov Region, local ecologists and representatives of the country's Ministry of Natural Resources and the Environment said.
"Dead fish was discovered in the Mechetka river last week. The cause of the incident could have been a lack of oxygen due to low water levels and the formation of a double-crust of ice on the surface" the statement issued by the ministry says.
The authorities have initiated an administrative investigation over the incident. Specialists of the Azov-Black Sea branch of the All-Russian Scientific Research Institute of Fisheries and Oceanography have taken samples of water and dead fish to establish the causes of its death