Large-scale Russian drone strikes on Sunday injured three civilians in Kyiv and at least two in Kharkiv, Ukraine’s second-largest city.

Ukraine said it struck a Russian air base on Saturday, while Russia continued to attack Ukraine with hundreds of drones overnight as part of a stepped-up bombing campaign that has dashed hopes for a breakthrough in efforts to end the more than 3-year-old war.

Russian President Vladimir Putin fired his transport minister on Monday following massive disruptions of Russian civilian airspace caused by Ukrainian drone raids. The Kremlin provided no specific details or reasons for the dismissal of Roman Starovoit,