A children's hospital in Mariupol, Ukraine, was destroyed Wednesday in what Ukrainian officials said was a targeted attack by Russian airstrikes, as the deputy mayor warned the hard-hit city is on the "brink of a humanitarian catastrophe."
At least three people, including a child, were killed in the airstrike, according to Ukrainian President Volodymyr Zelenskyy. Another 17 people, including women, children and medical workers, were wounded, he said.
The Ukrainian leader accused Russian state media of lying about the lack of patients inside the hospital at the time of the attack.
"War crimes are impossible without propaganda that covers them," Zelenskyy said in a televised address Thursday. "You will bear responsibility as well as those who give orders to throw bombs on peaceful people."
Zelenskyy had posted a video on social media Wednesday that he said showed the heavily damaged children's hospital and maternity ward in the southeastern Ukrainian port city.
"Direct strike of Russian troops at the maternity hospital," he said, calling on the international community again to impose a no-fly zone over Ukraine. "People, children are under the wreckage. Atrocity! How much longer will the world be an accomplice ignoring terror?"
Pavlo Kirilenko, the head of the Donetsk regional military administration, claimed in a post on Facebook that a Russian aircraft deliberately targeted the 600-bed hospital.
"City center maternity hospital, hospital, children's ward and therapy -- all destroyed during a Russian aviation flight to Mariupol," he said. "The Russians! You have not only crossed the border of unacceptable relations between states and peoples. You have crossed the line of humanity."
Russia's foreign ministry spokesperson Maria Zakharova claimed during a daily briefing Wednesday that Ukraine had put firing positions inside the children's hospital in Mariupol, though there is currently no evidence to support that allegation. The comment, however, appears to be an implicit acknowledgment that Russia deliberately targeted the hospital, as Kirilenko had claimed.
UNICEF Executive Director Catherine Russell said she was "horrified" by the reported attack on the hospital.
"We do not yet know the number of casualties but fear the worst," she said in a statement. "This attack, if confirmed, underscores the horrific toll this war is exacting on Ukraine's children and families. In less than two weeks, at least 37 children have been killed and 50 injured, while more than 1 million children have fled Ukraine to neighboring countries."
The besieged city, which sits on the Sea of Azov, has been without power or water amid steady Russian bombardments.
In a video conference Wednesday, Mariupol deputy mayor Serhiy Orlov said the city is on the "brink of a humanitarian catastrophe" and that "'Russia is trying to wipe Mariupol from the face of the earth."
Orlov reported that 1,207 people have died in the city because of shelling and aerial attacks -- and that half of those killed were ethnic Russians. Among the casualties was a child who died from dehydration, according to Zelenskyy.
The city has been burying its dead in a mass grave on the outskirts of Mariupol as it endures heavy shelling.
New satellite imagery collected by commercial satellite company Maxar Technologies on Wednesday morning, before the reported shelling of the hospital, showed extensive damage to civilian infrastructure in and around the city, including residential homes, high-rise apartment buildings, grocery stores and shopping centers.
Orlov accused Russia of indiscriminately bombarding the city because its forces were unable to break through its defenses, but he said that Mariupol would not surrender. He also called on the international community to impose a no-fly zone, an escalation that the White House and NATO allies have opposed.
"The Russian army cannot break our defenses and win on the ground, and this is why they are just bombing us relentlessly to break our spirit," he said. "Our spirit is strong but we need help. To the outside world we say: Help us save our city! Close the skies! Impose a no-fly zone!"'
ABC News' Patrick Reevell, Yulia Drozd and Christine Theodorou contributed to this report.