A number of explosions were heard on Friday in Ukrainain capital, Kyiv, as the Russian special military operation entered the second day.
Ukrainian President Volodymyr Zelenskyy said 137 civilians and military personnel have been killed so far in the Russian invasion of his country.
Zelenskyy says that despite Russia's claim it is attacking only military targets, civilian sites also have been struck.
Zelenskyy also signed a decree on Thursday ordering general mobilisation in the wake of Russia's military operation.
He said that it is to be carried out within 90 days.
Ukraine's Deputy Interior Minister Yevhen Yenin said explosions over Kyiv were caused by Ukrainian "anti-missile system shooting" a missile out of the sky, CNN reported, noting that the inputs were not independently verified.
Separately, Ukraine Foreign Minister Dmytro Kuleba said Kyiv was under attack from "horrific Russian rocket strikes."
"Last time our capital experienced anything like this was in 1941 when it was attacked by Nazi Germany. Ukraine defeated that evil and will defeat this one. Stop Putin. Isolate Russia. Severe all ties. Kick Russia out of everywhere," Dmytro Kuleba said in a tweet.
According to United States media reports, Russian mechanised forces that had entered Ukraine through Belarus were some 32 kilometers from Kyiv.
Russian troops launched their anticipated attack on Ukraine on Thursday, as President Vladimir Putin cast aside international condemnation and sanctions and warned other countries that any attempt to interfere would lead to "consequences they had never seen".
Several countries including the United Kingdom, the United States S, Canada, and the European Union have condemned Russia's military operations and imposed sanctions on Moscow.
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