Russia launched a large-scale missile attack across Ukraine, killing at least three people after hitting residential and industrial buildings, Ukrainian authorities said.
Two people were killed after a Russian missile hit vital infrastructure in Ukraine's western Khmelnytsky region, regional officials said.
At least six explosions were reported there, but officials did not provide immediate details about the damage.
Meanwhile, a 62-year-old man was killed outside the south-central city of Kryvyi Rih, where Governor Serhii Lysak said a shopping center and more than two dozen private buildings were damaged in the strikes.
“The crazy enemy has struck civilians again,” Lesak wrote on the messaging app Telegram. “Firing missiles at people.”
Oleksandr Vilkul, mayor of Kryvyi Rih, reported that 15,000 residents were without electricity and that local trams and trolleybuses were not running.
“The enemy is fiercely attacking peaceful cities,” Vilkul said.
Vilkol said that full information about the extent of the potential damage will be revealed after the end of the Russian attack.
All of Ukraine was under air raid warnings for more than three hours from around 6am local time (4am UK time) with the Ukrainian air force saying the country was under threat from several waves of cruise missiles.
The latest strikes come amid a cold wave sweeping Ukraine.
The goals of the Russian attack or the full scope of the strikes were not immediately clear.
There was no immediate comment from Moscow.
Anatoly Kortev, secretary of the Zaporizhia City Council in the southeast of the country, said via the Telegram application that the missile attack on the city led to casualties, but he did not provide further details.
Oleh Sinyhopov, governor of the eastern city of Kharkiv, said an industrial site and an educational facility were damaged after at least four missile strikes.
The city's mayor, Ihor Terekhov, said via the Telegram messaging app that at least one woman was injured in the raids on the city.
Meanwhile, four people were injured in the southeastern city of Zaporozhye, where its governor, Yuri Malashko, reported five explosions and said residential areas had been bombed.
“The missiles hit residential areas,” Malacho said on Telegram.
Read more from Sky News:
Putin praises “Russian warriors” on Orthodox Christmas Eve
Both sides have exhausted their ammunition, but one has the advantage
Military officials in other cities, including Dnipro in central Ukraine, said their cities had been subjected to a “massive missile attack” by Russia.
The attack comes as the governor of Russia's Belgorod region, about 19 miles from the border with Ukraine, said 300 people had been moved from the city after repeated Ukrainian strikes.
Evacuations began over the weekend.
Nearly two years into the war that Russia started with a full-scale invasion of Ukraine, both sides have turned to increased air strikes, having struggled to make significant gains along the front lines.
Russia launched some of its largest attacks on Kiev, as well as on Ukraine's second-largest city, Kharkiv.
The final blows are yet to come Russian President Vladimir Putin He pledged to support soldiers defending Russia's interests, and ordered his government to provide greater support to those fighting.
His comments came after Russia launched drone and missile attacks on Ukraine over the weekend, killing two people and wounding several others in the southern city of Kherson, while twelve people were wounded in a raid on Dnipro.
“Many of our men, our brave men, heroes, Russian warriors, even now, on this holiday, are defending the interests of our people,” the Russian President said, on the eve of Orthodox Christmas, Saturday, while meeting with the families of soldiers killed in Ukraine. A country that bears arms.