Vladimir Putin launched a large-scale missile attack across Ukraine at the start of peak morning hours on Monday, hitting residential and industrial facilities and injuring several people, Ukraine's officials said.
All of Ukraine was under air raid alerts from around 6am local time (0400 GMT) with Ukraine's Air Force saying the country was under several waves of cruise missile threat and, in some regions, ballistic missiles.
"Kyiv - shelter!" Ukraine's Air Force said on the Telegram messaging app, saying the capital was again under ballistic missile threat.
Ukraine's military officials in Kryvyi Rih, Zaporizhzhia, Kharkiv, Dnipropetrovsk and Khmelnytskyi have also said their cities were under a "massive missile attack" by Russia.
"The enemy is viciously attacking peaceful cities," said Oleksandr Vilkul, mayor of the southern Ukrainian city of Kryvyi Rih.
The targets of the Russian attack and the full scale of the strikes were not immediately clear but they have been stepped up in recent weeks.
It was also not clear if the air strikes were aimed at destroying electricity and water infrastructure, as previously to cause suffering for civilians during the winter, or defence production facilities.
There was no immediate comment from Moscow.
Anatoliy Kurtiev, secretary of the southeastern Zaporizhzhia city council, said a missile attack on the city resulted in injuries, but he did not provide further detail.
At least one woman was injured in an attack on Ukraine's second-largest city Kharkiv, Mayor Ihor Terekhov said. He said industrial facilities were hit, resulting in a fire.
Five blasts were heard in the city of Zaporizhzhia, regional governor Yuriy Malashko said, and at least two people were injured.
"Missiles hit residential areas," said Mr Malaskho.
Ukraine's military officials in other cities, including Dnipropetrovsk and Khmelnytskyi have also said their cities were under a "massive missile attack" by Russia.
Nearly two years into the war that Russia started with a full-scale invasion of Ukraine, both sides have shifted to increased air strikes at each other's territories, having struggled to make significant gains along the frontlines.
Russia has launched some of its largest attacks on Kyiv, as well as Ukraine’s second-largest city of Kharkiv.
But Ukraine has heavily targeted Russia-annexed Crimea, forcing Putin's Black Sea Fleet which was based in Sevastopol to retreat to other ports, as well as the Belgorod region of Russia.
British defence chiefs say Russian forces have recently made limited advances in the largely static frontlines but have suffered heavy casualties.
