Russian forces are firing at a nuclear research facility in the city of Kharkiv, the Ukrainian parliament said in a Twitter post on Saturday.
"It is currently impossible to estimate the extent of damage due to hostilities that do not stop in the area of the nuclear installation," the post quoted the State Nuclear Regulatory Inspectorate as saying.
The inspectorate's website did not contain any news about the attack.
Earlier this month the grounds of the Institute of Physics and Technology were hit by Russian shells. At the time, the facility's director general said the core housing nuclear fuel remained intact.
Kharkiv, Ukraine's second largest city, has seen some of the worst bombing since the conflict began on Feb. 24.
