The Ural River, which rises in the Ural Mountains and flows into the Caspian Sea, swelled several metres in just hours on Friday due to melt water, bursting through a dam embankment in the city of Orsk, 1,800 km (1,100 miles) east of Moscow.
Flooding has also been reported across Siberia, the Volga and central regions of Russia.
"An increase in air temperatures, active snow melt and river openings are predicted," Russia's emergency ministry said. "More than 10,400 residential buildings remain flooded in 39 regions."
