The Mariupol City Council, which published a photo of the destroyed building, said that Russian troops “purposefully and cynically destroyed the Drama Theater in the center of Mariupol.”
“The plane dropped a bomb on a house where hundreds of Mariupol civilians were hiding,” the report says.
CNN geolocated the image and confirmed it was a theater in a southeastern port city.
A video of the aftermath shows a fire raging in the ruins of the theater. Authorities say the number of casualties is unknown.
“The scale of this horrifying and inhumane act is still impossible to assess, because shelling of residential areas continues in the city,” they wrote on Telegram. “It is known that after the bombing, the central part of the Drama Theater was destroyed, the entrance to the bomb shelter in the building was destroyed,” the department added.
Petr Andruishchenko, an adviser to the mayor of Mariupol, described the theater as the largest “in number and size” shelter in the city center. “According to preliminary data, more than a thousand people were hiding there,” he said. “The probability of getting there to remove the rubble is low due to the constant shelling and bombing of the city.”
The city has no electricity, no water, no food, and residents are melting snow or dismantling heating systems for a drop of water, he said Tuesday.
Mariupol has been under siege by Russian troops since March 1. After weeks of unsuccessful attempts to create safe corridors for the evacuation of civilians, about 20,000 people were able to leave the city on Tuesday, Deputy Prime Minister of Ukraine Iryna Vereshchuk said.
The attack on the theater came just a day after a Ukrainian official blamed Russian troops for about 400 people being held captive in the Mariupol regional intensive care hospital.
“It is impossible to find words that could describe the level of cruelty and cynicism with which the Russian invaders destroy the civilian population of the Ukrainian city by the sea. Women, children and the elderly remain in the field of view of the enemy. unarmed civilians,” the city council said.
“We will never forgive and we will never forget,” he added.
The unfolding humanitarian catastrophe has drawn the ire of local authorities. “These bastards are trying [to] physically destroy Mariupol and the people of Mariupol, who were the symbol of our resistance,” Pavel Kirilenko, head of the administration of the Donetsk region, wrote on Facebook on Wednesday.
He says that “the fate of the hundreds of people who took refuge in the theater is unknown, as the entrance to the bomb shelter is littered with debris,” he said.
“The Russians are already lying, [saying] that the headquarters of the Azov regiment was located there. But they themselves are well aware that there were only civilians there,” he said.
After Russia bombed the maternity hospital on March 9, Russian Foreign Minister Sergei Lavrov alleged without proof that the hospital was the base of the ultra-nationalist Azov Battalion militia and that all the patients and nurses had left.
A spokesman for the Russian Defense Ministry later denied at a briefing that Russia fired at the maternity hospital at all, calling it a “provocation”.
Mariupol has become a war zone: On Tuesday, the city’s deputy mayor told CNN that Russia had fired missiles at the city, saying they counted 22 planes “that bombed our city and at least 100 bombs” on Monday.
Residents who fled the city described the conditions there as “unbearable” and “just hellish”. Shocking drone footage and satellite photos emerged on Tuesday showing plumes of thick smoke rising and collapsed buildings, highlighting the utter devastation caused by the Russian bombardment.
Ukrainian officials estimate that up to 2,500 civilians have died in Mariupol and hundreds of thousands of people are trapped in the city, with officials warning that those who remain are left without electricity, water and heat.
Ivana Kottasova of CNN, Jack Guy and Paul P. Murphy contributed to this article.