The Russian forces have made advancements in Melitopol and have captured the city's mayor. (File photo)
Here are the top 10 updates on this big story:
Air raid sirens were heard across most Ukrainian cities early on Saturday morning urging people to seek shelters, local media reported. Sirens were heard in the capital city of Kyiv, the western city of Lviv in Odessa, and Kharkiv, Cherkasy, as well as in the Sumy region in northeast of the country, a number of local Ukrainian media reported.
The Russian forces have made advancements in southern Ukraine's Melitopol and have captured the city's mayor. "A group of 10 occupiers kidnapped the mayor of Melitopol Ivan Fedorov," Ukraine's parliament said on Twitter. "He refused to cooperate with the enemy," it added.
The situation is grim in the southern port city Mariupol, which has been encircled and under constant Russian shelling. Mariupol has been without water and power for 11 days. The city's mayor says it is being shelled "every 30 minutes", with 1,200 civilians already dead and reports of people starving and of corpses in the streets.
Three missiles hit civilian buildings in the central city of Dnipro on Friday, destroying a shoe factory and killing one security guard. Dnipro had been considered a safe haven, suffering few attacks since Russia invaded Ukraine on February 24. A home for the disabled near Kharkiv was also bombed, with 330 people there at the time, officials say.
Russia on Friday announced that the military airfields of Lutsk and Ivano-Frankivsk, in western Ukraine closer to the Polish border, have been "put out of action".
With the Russian assault in its third week, President Volodymyr Zelenskiy, who has rallied his people with a series of addresses from Kyiv, said Ukraine had "already reached a strategic turning point". "It is impossible to say how many days we still have (ahead of us) to free Ukrainian land. But we can say we will do it," he said. "We are already moving towards our goal, our victory."
Russia, which has accused Ukraine of developing biological weapons with US help, said that the Kyiv regime is now "destroying evidence of military biological programmes" it was implementing. Both Washington and Kyiv have denied the existence of laboratories intended to produce biological weapons in the country.
Keen to avoid a direct military intervention in non-NATO Ukraine that they fear could trigger World War III, the US and its allies on Friday announced that they would end normal trade relations with Russia and announced a ban on imports of Russian vodka, diamonds and seafood. The US will also ban the export of US luxury goods to Russia and Belarus.
The Kremlin has invited "volunteers" including from Syria to fight alongside Russia's military in Ukraine, embroiling the Middle East in a conflict the West has worked to contain.
More than two and a half million people have fled the "senseless war" in Ukraine, the UN says -- more than half to Poland.
