Russia launched a massive attack on Ukraine overnight into Saturday with hundreds of drones, killing at least one person, 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.

Russia now controls more than two-thirds of Ukraine’s Donetsk region — the main theater of the ground war. Russian forces have carved out a 10-mile-deep pocket around the Ukrainian troops defending the crucial city of Kostiantynivka, partly surrounding them from the east, south and west.