Russia has stepped up its devastating attacks on major Ukrainian cities, with officials warning a "full-scale genocide" is under way.
Vladimir Putin unleashed a 15-hour artillery bombardment on the southern port city of Mariupol, while Kharkiv saw heavy shelling as Moscow troops continue their rampage towards capital Kyiv.
Sergiy Orlov, the deputy mayor of Mariupol, on the Black Sea, said whole districts have been levelled with the city surrounded by invading forces as artillery rains down.
He said medics cannot even get in to retrieve the dead as the Kremlin attempts to bomb the city into submission using "medieval" tactics.
"We are near to a humanitarian catastrophe," he said. "Russian forces are several kilometres away on all sides.
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"The Ukrainian army is brave and they will continue to defend the city, but Russia does not fight with their army, they just destroy districts...We are in a terrible situation."
The second city of Kharkiv saw a rocket striking a university building and police station in the early hours of Wednesday morning, followed by the city council.
For days it has been brutalised with missiles as Russia grows more and more desperate to claim a major scalp.
With plans to move through the country quickly before taking Kyiv within 48-hours when war was declared last Thursday fallen flat, Putin has changed tack.
Analysts have warned Russia, having suffered heavy losses against a much inferior military, is likely to begin surrounding cities and bombing them into submission.
Ukraine estimates it has seen 2,000 civilians killed.
If Mariupol falls, the thousands of defending troops in trenches along the frontline with Donetsk will be exposed, while Chernihiv, in the north east, and Sumy, in the east, could then follow suit.
Russia today gave the town of Konotop the ultimatum "surrender or be destroyed".
The strategic port city of Kherson in the south appears to have already fallen to the invaders after more heavy bombing with tanks seen rolling through the streets.
While Zaporizhzhia, home to Europe's largest nuclear power plant, has also been surrounded.
Ukraine's interior ministry had warned of a "nuclear catastrophe" if it was hit.
"An accident can happen like at the Chernobyl nuclear power plant or the Fukushima nuclear power plant," a ministry adviser said.
"Russian generals - think again! Radiation does not know nationalities, does not spare anyone."
Airstrikes, meanwhile, hit the HQ of the 95th Ukrainian armed forces brigade in Zhytomyr to the west of Kyiv.
The city of Bila Tserkva, 50 miles south of Kyiv, was also hit overnight.
Sergey Lavrov, the Russian foreign minister, warned that World War Three were to begin it would be "nuclear and destructive" in a thinly veiled attempt to get NATO involved.
Ukraine has said Moscow invaders are "trying to advance in all directions" but are "being resisted everywhere and suffering losses".
It estimates that 5,840 Russian troops have been killed so far.
Both sides are expected to hold further further talks, with a ceasefire on the table.
Moscow wants Ukraine banned from ever joining NATO, as well as a complete demilitarisation of the country.
