Temperatures in parts of Siberia plummeted to minus 50 degrees Celsius while blizzards blanketed Moscow in record snowfall and disrupted flights as winter weather swept across Russia.
In the Sakha Republic, located in the northeast part of Siberia and home to Yakutsk, one of the world's coldest cities, temperatures fell below minus 50C, according to the region's weather stations.
An abnormally early cold snap in Sakha pushed temperatures to even lower than minus 50C in several areas of Sakha, a vast region just a little smaller than India.
Almost all of Sakha is located in the permafrost zone. In the region's capital, Yakutsk, which lies about 5,000km east of Moscow, the temperature was around minus 44C to minus 48C.
Temperatures of minus 50C have become less common in recent years because of climate change, with permafrost showing increasing signs of thawing.
In the Russian capital, some of the biggest snowfalls ever seen caused delays at some airports on Monday, with runways covered in thick snow.
At least 54 flights were delayed and five more were cancelled at the capital's three largest airports, the RIA news agency reported.
Temperatures in Moscow were forecast to fall to about minus 18C later this week.