A boy has been killed after Russian shelling struck an apartment building, emergency services have confirmed.
An adviser to Ukraine's presidential office said more than 40 Ukrainian soldiers were dead and dozens wounded.
It's after Russia launched a full-scale invasion of Ukraine with explosions heard across major cities.
Harrowing images have been shared of civilians fleeing the capital of Kyiv, as well as families taking shelter in basements and subways.
Heroic firefighters were seen battling a blaze after an airstrike hit an apartment complex in Chuhuiv, in eastern Ukraine's Kharkiv region
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Bloodied civilians have been seen walking among the shrapnel, with a man mourning above the body of what is thought to be his son as the human toll of the war takes effect.
A cyclist was also hit by a shell in Uman, in the Cherkassy region and, according to reports, one civilian was killed with five others wounded.
Police sources have reported explosions as air raid sirens sounded as far west as Lviv.
Meanwhile, Russian troops are reported to be moving towards the town of Nova Kakhovka in Kherson Oblast.
A resident of the town of Chaplynka in the region told the Kyiv Independent that the mobilised Kremlin troops moving through from the Russian-annexed Crimea include tanks, armoured personnel carriers, and multiple rocket launchers as terrified families seek cover.
Ukrainian defence officials have also said that Kyiv's main international airport had come under a Russian bombing attack.
President Volodymyr Zelensky quickly announced Martial Law across all territories and he has called for all Ukrainians to fight the invaders if they're able to hold weapons.
Ksenya Michenka took cover with her teenage son in a metro station off Kyiv's Maidan Square and is reported as saying: "We need to save our lives.
"We hope the metro can save us because it is underground."
The roads are gridlocked out of the capital as terrified civilians plot their escape.
Prime Minister Boris Johnson has now said Russian military action in Ukraine was a "catastrophe for our continent" and he called for an urgent meeting of Nato leaders.
He will address the nation this morning where it's expected he'll announce tough sanctions on Vladimir Putin's Russia.
Speaking to BBC Radio 4's Today programme, General Sir Richard Shirreff, a retired Army officer, said any incursion into Nato territory would bring Britain into direct involvement in the conflict.
He said it is "entirely plausible" that Russian President Vladimir Putin could be aiming to revive the Soviet Union, adding that if Russia puts "one bootstep" into Nato territory, the entire alliance will be at war.
