Dozens of people were still missing on Wednesday after a Russian missile strike on a shopping mall in central Ukraine two days ago that killed at least 18.
Ukraine said Russia had killed civilians deliberately when it pounded the mall in Kremenchuk. Moscow said the mall was empty and it had struck a nearby arms depot.
"Russian missile hit this location precisely. De-li-be-ra-te-ly ... It is clear that Russian killers received those exact coordinates," Ukraine's President Volodymyr Zelenskiy said in an evening video address. "They wanted to kill as many people."
Authorities said around 36 people were still missing.
Further east in Lysychansk in the Luhansk region, a key battleground in Russia's assault on the industrial heartland of Donbas, the governor reported increased military action.
The situation in Lysychansk resembles that in its twin city Sievierodonetsk more than a month ago when the Russians started taking building after building, Luhansk Governor Serhiy Gaidai said on Wednesday. Sievierodonetsk fell to Russia on Saturday.
"The situation in Lysychansk is very difficult," Gaidai said earlier on television.
"The Russians are using every weapon available to them ... and without distinguishing whether targets are military or not - schools, kindergartens, cultural institutions," he said.
"Everything is being destroyed. This is a scorched-earth policy."
Russian forces are trying to surround Lysychansk, Ukraine's armed forces general staff said on Wednesday.
The mayor of the southern city of Mykolaiv, Oleksandr Senkevych, said a multi-storey residential building had been hit this morning and rescuers were working there.
Russia has denied targetting civilian areas during its four-month offensive against Ukraine. The UN says at least 4,700 civilians have been killed since Russia invaded on February 24.
In the Dnipropetrovsk region, towards Ukraine's east, Governor Valentyn Reznychenko said bodies of a man and a woman had been found buried under the rubble of a transportation company office that was hit by a Russian missile on Tuesday.
He had earlier said that Russia had fired six missiles on Tuesday in the region, three of which were shot down.
Reuters could not verify the account. The Russian Defence Ministry did not reply to an emailed request for comment.
Separately, Russia-installed officials said their security forces had detained Kherson city mayor Ihor Kolykhayev on Tuesday after he refused to follow Moscow's orders. A local official said the mayor was abducted.
Kherson, a port city on the Black Sea, sits just northwest of the Russian-annexed Crimean peninsula.
In the past few days, Ukrainians have also described attacks in the southern region of Odesa and Kharkiv in the northeast.
The Russian invasion, the biggest assault on a European state since World War Two, has driven up prices of food and energy worldwide and fuelled global security worries.
Finland and Sweden on Tuesday moved a step closer to joining the Western NATO military alliance, whose members have provided Ukraine with weapons, after Turkey dropped its opposition to their membership.
The development solidifies the alliance's response to Russia - particularly in the Baltic Sea, where Finnish and Swedish membership would give NATO military superiority.