Live updates: follow the latest news on Russia-Ukraine
UN Secretary General Antonio Guterres said he was “appalled” by reports more than 60 people were feared dead after a Russian bomb hit a school in Ukraine that is being used as a shelter.
The bomb struck the school in Bilohorivka, in the eastern Luhansk region, which then caught fire on Saturday, officials said.
Mr Guterres called it a reminder that “it is civilians who pay the highest price” in war.
It came as Moscow's forces intensified their attack on Mariupol’s steel plant in what appeared to be a race to capture the city before Russia’s Victory Day holiday.
Authorities said about 90 people were sheltering in the basement. Emergency crews found two bodies and rescued 30 people, but “most likely all 60 people who remain under the rubble are now dead,” Serhiy Haidai, governor of Luhansk province, wrote on the Telegram messaging app.
Russian shelling also killed two boys, aged 11 and 14, in the nearby town of Pryvillia, he said. Luhansk is part of the Donbas, the industrial heartland in the east that Russia’s forces are working to capture.
As Moscow prepared to celebrate the 1945 surrender of Nazi Germany with a Victory Day military parade on Monday, a line-up of Western leaders and celebrities made surprise visits to Ukraine in a show of support.
US first lady Jill Biden met her Ukrainian counterpart, Canadian Prime Minister Justin Trudeau raised his country’s flag at its embassy in Kyiv, and U2’s Bono, alongside bandmate The Edge, performed in a Kyiv subway station that had been used as a bomb shelter, singing the 1960s song Stand By Me.
The acting US ambassador to Ukraine, Kristina Kvien, posted a picture of herself at the American Embassy, and described plans for the eventual US return to the Ukrainian capital after Moscow’s forces abandoned their effort to storm Kyiv weeks ago and began focusing on the capture of the Donbas.
Ukrainian President Volodymyr Zelenskyy and others gave warnings in recent days that Russian attacks would only worsen in the lead-up to Victory Day, and some cities declared curfews or cautioned people against gathering in public. Russian President Vladimir Putin may want to proclaim some kind of triumph in Ukraine when he addresses the troops on Red Square.
“They have nothing to celebrate tomorrow,” Linda Thomas-Greenfield, US ambassador to the UN, told CNN. “They have not succeeded in defeating the Ukrainians. They have not succeeded in dividing the world or dividing Nato. And they have only succeeded in isolating themselves internationally and becoming a pariah state around the globe.”
Russian forces struggled to complete their takeover of Mariupol, which has been largely reduced to rubble. The sprawling seaside steel mill where an estimated 2,000 Ukrainian fighters were making what appeared to be their last stand was the only part of the city not under Russian control.