A Russian "guided bomb" has hit a blood transfusion centre in north-eastern Ukraine, killing two people and injuring four, Ukrainian officials say.
Volodymyr Zelensky posted an image of the building on fire as a result of Saturday night's attack around Kupiansk, in the Kharkiv region.
"This war crime alone says everything about Russian aggression," he said.
Russia has not commented. It has previously denied all allegations of targeting civilians - or war crimes.
The city of Kupiansk and nearby settlements were seized by Russian troops in the first few days of Moscow's full-scale invasion of Ukraine, launched in February 2022.
The area was liberated during a Ukrainian counter-offensive last September, but comes under missiles and shelling daily.