MOSCOW/KYIV (Reuters) -A major Soviet-era dam in the Russian controlled part of southern Ukraine was breached on Tuesday, unleashing floodwaters across the war zone in what both Ukraine and Russia said was an intentional attack by the other's forces.
Unverified videos on social media showed water surging through the remains of the dam with bystanders expressing their shock, sometimes in strong language. Water levels raced up by metres in a matter of hours.
The dam, 30 metres (yards) tall and 3.2 km (2 miles) long and which holds water equal to the Great Salt Lake in the U.S. state of Utah, was built in 1956 on the Dnipro river as part of the Kakhovka hydroelectric power plant.
It also supplies water to the Crimean peninsula, annexed by Russia in 2014, and to the Zaporizhzhia nuclear plant, which is also under Russian control and which gets cooling water from the reservoir.
The International Atomic Energy Agency (IAEA) said there was no immediate nuclear safety risk at the plant due to the dam failure but that it was monitoring the situation closely. The head of the plant also said there was no current threat to the station.
Ukrainian President Volodymyr Zelenskiy blamed Russia for the damage.
"The destruction of the Kakhovka hydroelectric power plant dam only confirms for the whole world that they must be expelled from every corner of Ukrainian land," Zelenskiy wrote on the Telegram messaging app.
Ukraine's military said that Russian forces blew up the dam.
Russian-installed officials in Kherson said Ukraine struck the dam at 2300 GMT several times, destroying the hydraulic valves of the hydroelectric power station but said the dam was not totally destroyed.
"We ask all residents of coastal settlements to be ready for evacuation," the Russian-controlled region said. "Emergency and special services of the region are in full readiness and will provide all necessary assistance."
Reuters was unable to immediately verify the battlefield accounts from either side.
It was not immediately clear how the flood waters would affect Ukraine's long planned counter-offensive against Russian forces who are dug in across southern and eastern Ukraine.
(Reporting by Lidia Kelly in Melbourne, Guy Faulconbridge in Moscow and Valentyn Ogirenko in Kyiv; Editing by Edmund Klamann and Michael Perry)