Ukrainian officials accused Russia damaging a cancer hospital and several residential buildings in the southern city of Mykolaiv with shelling from heavy artillery.

The hospital’s head doctor, Maksim Beznosenko, said several hundred patients were in the hospital during the attack but that no one was killed. The assault damaged the building and blew out windows.

Russian forces have stepped up their attacks on Mykolaiv, located 470 kilometers (292 miles) south of Kyiv, in an attempt to encircle the city.

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Ukrainian and Western officials earlier accused Russia of shelling a maternity hospital in the southern city of Mariupol on Wednesday. Three people died in that attack.