Floods in the Russian city of Orenburg have raised water levels to two metres above critical, leaving just the roofs of some houses showing.
The city’s mayor urged many residents to leave home, as sirens sounded.
Levels in Orenburg are likely to peak on Friday, but floods are expected to spread through neighbouring regions over the coming days and weeks.
Kazakhstan has also been badly affected, with 100,000 people evacuated from their homes in the last week.
The flooding is being described as the worst to hit the region in 80 years.
Last week, several rivers – including the Ural, Europe’s third-largest – burst their banks. A number flow back and forth between Russia and Kazakhstan.
High seasonal temperatures have led to rapidly melting snow and ice, compounded by heavy rains.
The Ural river reached 11.43m (37ft) in Orenburg on Friday. Authorities say that more than 10,000 people have been evacuated there, and 11,700 homes have been flooded.
