Russia and Ukraine have exchanged hundreds more prisoners as part of a major swap after an overnight attack on the Ukrainian capital that injured at least 15.

Russia launched 250 drones and 14 ballistic missiles against Kyiv, Ukraine's air force said, causing fires in residential buildings. It was one of the biggest combined aerial assaults on the city since the war began. The air force said it had downed six missiles and 245 drones.

Russia and Ukraine each exchanged 307 of their service personnel on Saturday on the second day of a prisoner exchange that, when completed, is set to be the largest such swap in the three-year war between the two countries.