Video footage shows shocked survivors, who had been inside sheltering from the airstrike, moments after the attack, reports ITV News Correspondent John Ray
The first images from inside a theatre in Mariupol that was hit by a Russian airstrike have emerged.
Footage shows the immediate aftermath of the attack, with women and children covered in dust evacuating the badly damaged venue.
Another video shows part of the three-storey building, which was being used as a bomb shelter by civilians in the encircled port, had completely collapsed after being struck by Russian missiles on March 16.
As many as 300 people are feared dead after the attack.
Video shows the parts of the three-storey theatre were completely destroyed
The theatre was attacked by Russian troops despite the word 'children' being written in Russian in large letters outside the venue.
Between 1,000 and 1,500 people were sheltering in the theatre, it was reported. While some people managed to escape, others were left trapped.
In footage, a male voice can be heard saying: “It’s the aftermath shelling on drama theatre, the rocket hit the very centre of the drama theatre, now people are trying to evacuate.”
Ukraine's Foreign Affairs Minister Dmytro Kuleba called the assault "another horrendous war crime", which targeted "hundreds of innocent civilians" in hiding.
Mariupol has come under heavy bombardment in the month since the Russian invasion. Local officials report 80-90% of all structures in Mariupol have been damaged.
An estimated 300,000 remained trapped in the city with no running water, electricity or gas.
ITV News Correspondent Geraint Vincent, in Lviv, western Ukraine, on the details emerging from Mariupol following the theatre attack
Drone footage of Mariupol released earlier this week by the Ukrainian National Guard shows the extent of the devastation in the port city which has been under heavy bombardment since the Russians invaded a month ago.
The attack on the theatre is one of many reports of Russia targeting civilians in Ukraine - something Moscow has continued to deny.
Missiles struck a maternity hospital in Mariupol, which left several people dead including a pregnant woman and a baby while 21 people died after a school and a community centre were struck by Russian missiles in the northeastern city of Merefa in Ukraine.
The devastating attacks have prompted the evacuation of many residents from the besieged city, where charities have warned that food and water supplies have been running dangerously low.
Yelezar Grankov was a doctor working in a hospital in Mariupol in the first couple of weeks of the invasion, while his wife and young daughter were at home.
But he described how the security situation rapidly deteriorated in the southern port city, prompting him and his family to flee for safety on March 16.
"For the first week we have water... we buy some food to our home," he told ITV News. "But when we leave Mariupol there is no water, there is no warmth... we drank water from the snow. It was so difficult for my family. "
'We drank water from the snow,' Mr Grankov said
Mr Grankov says his daughter sometimes starts crying when his wife goes to another room as she is afraid of attacks from Russian forces after they destroyed much of the southern city.
Meanwhile, Boris Johnson has had a “frank and candid discussion” with China’s President Xi Jinping about the situation in Ukraine, Downing Street has said.
The call came after Nato leaders urged Beijing to “abstain” from supporting Russia’s war effort and to refrain from any actions that would help it circumvent sanctions.
In a terse readout following the 50-minute call, a No 10 spokesman said they had discussed “a range of issues of mutual interest” including the situation in Ukraine.
US President Joe Biden visited Poland on Friday in a bid to reaffirm the US' commitment to protect a key NATO member on Ukraine’s doorstep.
His two-day visit follows a trio of emergency summits in Brussels and brought him to the country that has accepted the lion’s share of the more than 3.5 million people who have fled Ukraine.
More than 2.2 million refugees have entered Poland since the start of the month-old war, and many propose to stay there.
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