A dam burst in the Russian Urals mountain city of Orsk on Friday and an evacuation is underway, local emergency services said.
State news agency TASS quoted the emergencies ministry as saying that up to 4,000 houses accommodating 10,000 residents of a suburban area of Orsk, which has total a population of around 230,000, could be inundated as a result of the dam breach.
Local emergency services said in a statement that they were working to evacuate residents and shore up the dam in Orsk, which is around 1,800 km (1,115 miles) east of Moscow, skirting the border with Kazakhstan.
Unverified footage circulating on the Telegram messenger app appeared to show water gushing through a break in a low-slung, earthen dam.
A state of emergency has been declared in the Orenburg region, the emergencies ministry said, and ministry personnel had helped 3,500 people affected by flooding nationwide in recent days.