Officials say a Russian drone has blasted a hole in an apartment building in northeastern Ukraine during a nighttime attack, killing at least four people and injuring nine others.

The Security Service of Ukraine (SBU) and Ukraine’s Special Operations Forces (SOS) struck the Ryazan Oil Refinery and the Ryazan Thermal Power Plant in an overnight drone strike on Jan. 24, an SBU source told the Kyiv Independent. The attack was later confirmed by the General Staff of Ukraine’s Armed Forces.