About 16 explosions were heard overnight on Jan. 16 in Voronezh, a city in southwestern Russia, TSN reported citing local social media posts.
Russian authorities said they 'repelled an attack' and downed three drones.
Earlier on Jan. 15, explosions were reported in Kursk, also a Russian city near the border with Ukraine.
Ukraine has relied on UAVs to strike targets within Russia, mostly border cities.
In December 2023, Ukraine launched 70 drones against Russian targets, as a "response to Russia's terrorist attacks on Ukrainian cities and civilians".