Ukraine's nuclear agency said on Friday it was recording increased radiation levels from the site of the defunct Chernobyl nuclear power plant.
Presidential advisers meanwhile said President Volodymyr Zelenskiy was still in the capital Kyiv.
"The base scenario of Russia's special operation is clear. The sole goal - to take Kyiv and kill Ukraine's authorities, President Zelenskiy personally," said an adviser to the Ukrainian presidential office, Mykhailo Podolyak.
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