Officials say a Russian drone barrage has targeted the center of Kharkiv, injuring nine people and damaging a maternity hospital in Ukraine’s second-largest city.

Russia launched its largest drone and missile bombardment of Ukraine overnight into Wednesday, according to Ukrainian President Volodymyr Zelenskyy.

Ukraine’s Security Service said Sunday they had killed Russian special service agents suspected of gunning down a fellow officer in Kyiv earlier this week, saying it believed Russia’s Federal Security Service was responsible.