Ukraine's military spy agency GUR struck a main production facility of a Russian aviation factory in Russia's Voronezh region, a Ukrainian intelligence source told Reuters.
Russia's defence ministry said earlier on Tuesday that two drones were downed over the region.
The source said the 711th aviation repair plant in the town of Borisoglebsk was hit. It did not provide any details of the scale of the damage.
The town is at least 350 kilometres away from the Ukrainian government-held side of the front line in the northeast.
Reuters could not independently verify the accounts.
Kyiv has recently stepped up attacks deep in Russia's territory, targeting military facilities and energy infrastructure that helps Moscow's war effort. It mostly uses various types of long-range domestically produced drones.