Russia shot down 51 Ukrainian drones from above several regions, including near the border, Moscow's defence ministry said on Sunday.
Eighteen were intercepted in the Tambov region, about 400 kilometers (250 miles) from the Ukrainian border, and 16 in the area of the border town Belgorod, the ministry said in a statement on Telegram.
The others were shot down in the regions of Oryol, Briansk, Lipetsk and Voronej.
One was intercepted in the Kursk region, where Ukrainian troops have been conducting a ground offensive since August and control several hundred square kilometres of Russian territory.
Russia announces almost daily that it has destroyed Ukrainian drones.
Kyiv claims that the strikes, which often target energy infrastructure, are in response to Russian bombardments of Ukrainian territory.