20,000 tonnes of diesel oil leaked into a river within the Arctic Circle, after that incident, Russia’s President Vladimir Putin has declared a state of emergency.
Last Friday due to an accident, when a fuel tank at a power plant near the Siberian city of Norilsk collapsed, the spill happened.
The director of power plant Vyacheslav Starostin has been taken into custody until 31 July, but he was not yet charged.
Norilsk Nickel, which is the world’s leading nickel and palladium producer, the plant is a subsidiary of it.
The report of the news was reportedly delayed for two days in informing the Moscow authorities about the spill.
The Russian Investigative Committee (SK) has also launched a criminal case over the pollution and alleged negligence of reporting it late.
President Putin also expressed anger after knowing that the concerned officials only learnt about the incident on Sunday.
The Arctic permafrost has been melting in exceptionally warm weather for this time of year.
The ground subsidence beneath the fuel storage tanks is believed to have caused the spill.