Russian Orthodox Christians have been plunging into the river in Moscow through a hole in the ice as part of an annual ritual.
The age-old ritual commemorates the baptism of Jesus Christ in the Jordan River, or the Epiphany, which the Russian Orthodox Church celebrates today.
Many of those who braved the minus 13°C temperatures also believe that taking a dip in freezing cold water has health benefits.
The authorities in Moscow have been battling a major fire at a huge skyscraper in the city.
It broke out on the 66th floor of the Federation Tower- which is still under construction.
It is designed to be Europe's tallest building.
U.N.-Arab League envoy Kofi Annan is in Moscow for talks with President Dmitry Medvedev of Russia, which has crucial influence over diplomatic efforts to end the bloodshed in Syria.
Peace envoy Kofi Annan is seeking to shore up support for his efforts to end a year of fighting in Syria where 8,000 people have been killed in an anti-government uprising.