Father missing under snow; more than 200 people continue search and rescue at -23C, snowstorm and bleak light of polar night.
The exact reason of the leak is yet to be established, but a statement from Norilsk Nickel company, which operates the site suggests it could have been caused - worryingly - by collapsing permafrost.
Summer seems like it was just yesterday.
All Topics
All Countries
Any Date
Apply