Vladimir Putin's missiles pounded Kharkiv last night in more heavy shelling on Ukraine as the US warned Russia could be prepared to unleash biological weapons on the country.
Disturbing footage appears to show a series of shocking explosions on the city with another video showing the aftermath.
Civilians run to safety amid the horrifying blasts in the unverified footage believed to show shelling in Kharkiv.
Troops appeared to search the inside of a shopping centre in the city in another clip.
It comes as White House press secretary Jen Psaki said the world should be "on the lookout" for the Russian use of chemical and biological weaponry.
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She said "Russia's false claims" about alleged US biological weapons labs and chemical weapons development in Ukraine could be an "an obvious ploy" by the Kremlin to try to "justify its further premeditated, unprovoked, and unjustified attack on Ukraine".
UK minister Mr Heappey warned Mr Putin that the use of chemical weapons had "triggered an international response" in the past.
He told Today their deployment was the "most despicable thing that anybody can imagine" and that the scenes being witnessed in Mariupol would be "nothing by comparison to the suffering and devastation that chemical weapons cause".
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His comments come with talks set to take place between Moscow and Kyiv foreign ministers in Turkey in what will be the highest-level discussions since the assault started last month.
The UK's armed forces minister has today said the "despicable" bombing of a maternity hospital in Ukraine is a war crime committed by Russian troops.
Ukrainian President Volodymyr Zelensky said the strike in Mariupol was part of a "genocide" on his people.
Three people, including a child, were killed in the attack, according to the besieged city's council.
Defence minister James Heappey told BBC Radio 4's Today programme that UK intelligence believes the strike came from artillery rather than the air, but that Britain is "still looking at exactly (what happened)".
The Army veteran said that, even if Russian troops did not deliberately target the medical complex, the attack - which Prime Minister Boris Johnson has described as "depraved" - still amounts to a war crime.
