Ukraine says Russian forces blew up the Kakhovka dam on the Dnipro River. Meanwhile, Ukrainian President Volodymyr Zelenskyy praised troops for advances claimed near Bakhmut.
The Kakhovka dam in southern Ukraine has been blown up, Ukrainian and Russian officials said on Tuesday, threatening to flood areas downstream along the Dnipro River.
The Soviet-era hydroelectric plant also supplies water to the Crimean peninsula, which was annexed by Russia in 2014, and to the Zaporizhzhia nuclear plant, which is also under Russian control.
"The Kakhovka [reservoir] was blown up by the Russian occupying forces," the South command of Ukraine's Armed Forces said on Tuesday morning on its Facebook page.
"The scale of the destruction, the speed and volumes of water, and the likely areas of inundation are being clarified."
The Ukraine's Kherson regional administration said that the water level would reach a critical level in five hours and began evacuating the population from dangerous areas.
Videos on social media appeared to show significant damage to the dam.
The Moscow-installed mayor of the nearby town of Nova Kakhovka initially denied social media reports that the dam had been blown up, but later said the dam had been shelled in "a serious terrorist act."
Russian emergency services said around 80 settlements downstream could be affected.
Russia's state news agency TASS reported that there was not yet any "critical danger" posed to the Zaporizhzhia nuclear plant..
Russia launches overnight air attack
Air defense systems were engaged in repelling air attacks in Kyiv and the Kyiv region region early on Tuesday, the military administration of the Ukrainian capital said on the Telegram messaging app.
Vitali Klitschko, mayor of the Ukrainian capital, also said that blasts heard in Kyiv were the sound of air defense systems repelling an attack.
After the attack, the Kyiv military administration said that air defenses destroyed more than 20 enemy objects.
Air raid alerts were in effect across all of Ukraine overnight as Russia launched another wave of airstrikes on Ukrainian cities.
Zelenskyy hails advances as Russia says offensive repelled
Ukrainian President Volodymyr Zelenskyy on Monday praised his troops for advances claimed near the devastated city of Bakhmut, while Russia said it had repelled a large-scale attack.
Zelenskyy welcomed what he called, "the news we have been waiting for" during his nightly video address to the Ukrainian people.
"I am grateful to each soldier, to all our defenders, men and women, who have given us today the news we have been waiting for. Fine job soldiers in the Bakhmut sector!" he said.
Zelenskyy went on to praise the actions of Ukrainian troops who, "skillfully, decisively and effectively defend our positions, destroy the occupiers and, most importantly, move forward." The president also said Russia was reacting "hysterically" to Ukrainian forces.
Meanwhile, Russia's Defense Ministry claimed early on Tuesday that it had thwarted another major offensive by Ukrainian forces in Donetsk, inflicting huge personnel losses and destroying eight main battle Leopard tanks.
