Russian shelling damaged a nuclear research facility in the northeastern Ukrainian city of Kharkiv on Saturday, the State Nuclear Regulatory Inspectorate said.
The strike damaged some of the site's buildings and infrastructure but did not affect the area housing nuclear fuel and radiation levels there are within a normal range, it said in an online post.
"The probability of new damage ... which can directly affect the state of nuclear and radiation safety, remains high due to shelling by Russian troops," it said.
Reuters could not independently verify the inspectorate's account on the incident.
Ukraine's second-largest city suffered heavy bombardment in the first few months of the war, but weeks of relative calm have recently been broken by renewed shelling.
(Reporting by Max Hunder; Writing by Alessandra Prentice; Editing by Frank Jack Daniel)