Pro-Kremlin officials were pulling out of the key southern Ukraine city of Kherson on Wednesday, as Kyiv's forces advanced on territory in Russian hands since the war's earliest days.
Kherson was the first major city to fall to Moscow's troops after the February invasion and retaking it would be a major prize in Ukraine's ongoing counteroffensive.
Kyiv's recapturing of swathes of its territory in the east and parts of the south has however been followed by punishing missile and drone strikes that have demolished large parts of Ukraine's power grid ahead of winter.
"The entire administration is already moving today," to the left bank of the Dnipro River, the region's Moscow-installed head Vladimir Saldo, said on Russian state television.
The city is located on the western bank of the Dnipro, the same side where Ukrainian troops have been moving forward in a counter-offensive that began in August.
Saldo said the pull-out, along with the organized movement of civilians from the city, was a precaution and vowed that Russian forces would continue to fight against Ukraine.
Pro-Russian officials have said civilians would only be allowed to leave toward Russia or Russian-held parts of Ukraine.
Ukrainian forces have targeted bridges across the river to disrupt supply lines so Russian-installed officials said the evacuations were being done with ferries.
Russia's Rossiya 24 state television channel showed images of people waiting to board ferries to cross the river.
Local officials said they were planning to evacuate up to 60,000 civilians from the city of Kherson over a period of around six days.
Ukraine has re-captured large swathes of occupied territory in the east of the country in recent weeks.
Its advance on the southern front has been far slower but has been gaining momentum in recent days.
Russia's military commander for Ukraine operations, General Sergei Surovikin, on Tuesday said the Russian army would ensure "the safe evacuation of the population."
Surovikin said Ukrainian strikes targeting civilian infrastructure "create a direct threat to the lives of residents."
"The situation in the area of the special military operation can be described as tense. The enemy is not abandoning its attempts to attack Russian troop positions," he told Rossiya 24.
There have also been some Russian advances.
Russian forces on Tuesday claimed to have retaken territory from Ukrainian troops in the eastern Kharkiv region.
It was Moscow's first announced capture of a village there since being nearly entirely pushed out of the region last month.
Russian forces also continue to occupy the Zaporizhzhia nuclear power plant in a different section of the Dnipro River.
Petro Kotin, head of Ukraine's nuclear energy agency Energoatom, told AFP on Wednesday that Russian forces were holding prisoner "about 50" plant employees.
Warning of power outages
Ukraine meanwhile scrambled to rebuild damaged energy facilities across the country following a series of Russian strikes.
Ukraine has warned of an emerging "critical" risk to its power grid after repeated Russian bombardments had destroyed one-third of the country's power facilities as winter approaches, according to the presidency.
"It's necessary for the whole country to prepare for electricity, water and heating outages," Kyrylo Tymoshenko, deputy head of the Ukrainian president's office, told Ukrainian television on Tuesday.
Drones also bombarded Kyiv on Monday, leaving five dead, in what the presidency described as an attack of Russian desperation after a string of battlefield losses.
Kyiv and its Western allies have accused Moscow of using Iranian-made drones in the strikes, a move President Volodymyr Zelensky portrayed as a sign of Russia's failure.
The Kremlin said Tuesday it had no knowledge of its army using Iranian drones in Ukraine and Tehran has said the claims that it is providing Russia with weapons are "baseless."