Russia bombarded Ukraine’s second-largest city with massive strikes in the early hours of Saturday, its mayor said, killing at least three people, one night after Moscow carried out one of the war’s largest aerial assaults on Ukraine.

Photos showed burnt and partially destroyed houses and vehicles, and rescuers carrying the injured to safety and removing debris.

Russian officials said Sunday that Moscow is still awaiting official confirmation from Ukraine that a planned exchange of 6,000 bodies of soldiers killed in action will take place, reiterating allegations that Kyiv had postponed the swap. On the front line in the war, Russia said that it had pushed into Ukraine’s Dnipropetrovsk region.