Kyrylo Budanov, head of Ukraine's military intelligence (HUR), published the identities of the Russian military brigades responsible for the deadly attack on Sumy on April 13.

Budanov reported that the Russian 112th and 448th missile brigades attacked the city of Sumy with two Iskander-M ballistic missiles.
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The attacks were launched from Russia's Voronezh and Kursk oblasts, specifically from the Liski and Lezhenski settlements, respectively, Budanov said.

Multiple officials, including Presidential Office Head Andrii Yermak and U.S. Ambassador Bridget Brink, reported that Russia used cluster munitions in the attack on Sumy.

The use of cluster munitions in civilian areas is considered a violation of international humanitarian law. Many international leaders have denounced Russia's attack, calling it a war crime.

https://kyivindependent.com/ukraines-intelligence-reveals-russian-brigades-responsible-for-sumy-attack/

The screws on Russia must be urgently tightened through fresh sanctions after the devastating attack against the Ukrainian city of Sumy, foreign ministers of the European Union said as they gathered for a meeting in Luxembourg on Monday. Two Russian ballistic missiles struck Sumy as the Christian faithful celebrated Palm Sunday, a festivity that honours Christ's entrance into Jerusalem. At least 34 people were killed and more than 110 were injured.

…The attack against civilians came as Ukraine was still mourning 19 people, including nine children, who were killed in Kryvyi Rih earlier this month. Both Russian strikes bear similarities, combining ballistic missiles and cluster munitions to maximise damage.

For foreign ministers, the barrage demonstrates Vladimir Putin has no interest in pursuing the peace negotiations promoted by Donald Trump.

"I just want to say how appalled I am by the latest spate of Russian attacks on Ukraine," Radosław Sikorski, Poland's foreign minister, said on Monday. "I hope President Trump and the US administration see that the leader of Russia is mocking that goodwill and I hope the right decisions are taken."

https://www.euronews.com/my-europe/2025/04/14/putin-is-mocking-trump-eu-foreign-ministers-call-for-new-sanctions-on-russia-after-sumy-at