According to Ukraine’s State Emergency Service, 117 people were wounded in the morning attack, which involved ballistic missiles armed with cluster munitions. Fifteen children were among the injured.
Ukrainian President Volodymyr Zelensky urged Western nations to respond decisively.
"There must be pressure on Russia to end the war and guarantee security for people," Zelensky said on the X social media portal.
"Without truly strong pressure, without sufficient support for Ukraine, Russia will continue dragging this war out. It’s now the second month that Putin has been ignoring the U.S. proposal for a full and unconditional ceasefire," the Ukrainian head of state added.
Andriy Yermak, head of Ukraine’s presidential office, said the use of cluster munitions showed intent to maximize civilian casualties.
"The Russians are doing this to kill as many civilians as possible," he said.
Commenting on the attack, Polish Prime Minister Donald Tusk said it exemplified "the Russian version of a ceasefire."
The European Commission’s president, Ursula von der Leyen, denounced the strike as a "barbaric attack, made even more vile as people gathered peacefully to celebrate Palm Sunday."
She added, "This latest escalation is a grim reminder: Russia was and remains the aggressor, in blatant violation of international law."
US officials echoed the condemnation.
Keith Kellogg, President Donald Trump's envoy for Ukraine said the "attack by Russian forces on civilian targets in Sumy crosses any line of decency."
"As a former military leader, I understand targeting, and this is wrong. It is why President Trump is working hard to end this war," the retired lieutenant general said.
US Secretary of State Marco Rubio also issued a statement: "The United States extends our deepest condolences to the victims of today’s horrifying Russian missile attack on Sumy."
Ukraine’s Deputy Foreign Minister Andrii Sybiha said Kyiv was "sharing detailed information about this war crime with all of our partners and international institutions."
He added that the International Criminal Court, which Ukraine officially joined this year, is investigating high-profile war crimes in the conflict.
(ał)
Source: IAR, PAP, Reuters