Russia said Saturday it had evacuated more than 4,000 people in the Orenburg region, which lies near the Kazakhstan border, due to flooding after a dam burst.

Emergency services had been working through the night after a dam burst in the city of Orsk, near the border with Kazakhstan.

The press service of the Orenburg governor said "4,208 people, including 1,019 children" had been evacuated and more than 2,500 homes were affected by the flooding after a dam burst on Friday following torrential rain.

Russia opened a criminal case on "negligence and violation of construction safety rules" into the burst of the dam, built in 2014.

Authorities said the situation was difficult throughout the region, warning of a dangerous water level on the Ural river in the main city of Orenburg.

Governor Denis Pasler said the flood had reached its "peak", saying the situation was especially difficult in Orsk.

Russian emergency services published images of rescue workers going through villages on boats and hover crafts.

Kazakh President Kassym-Jomart Tokayev said the floods were one of the worst natural disasters in Kazakhstan in 80 years.

He called for authorities in the Central Asian country to be ready to help those affected.

Several regions in the Urals and western Siberia have been affected by floods at the start of spring.