Ukrainian drones successfully struck a helicopter base in Sochi and an aircraft factory in Smolensk on Oct. 1, according to reports by Russian Telegram channels and Ukrainska Pravda.
Videos posted on local Russian social media channels showed smoke and explosions near Sochi's Adler airbase, but it was unclear what the extent of the damage was at the time of this publication.
Ukrainska Pravda later reported, citing its source in the intelligence services, that Ukraine's military intelligence (HUR) was behind the attack.
The aircraft factory in Smolensk which appears to have been the target of the attack is part of the state-run Tactical Missile Armament corporation.
Drone attacks have become commonplace both in occupied Crimea and in Russia itself. On Aug. 30, a drone strike destroyed four Il-76 aircraft in Pskov Oblast, and marine drones took part in a large-scale attack on a shipyard in occupied Sevastopol, Crimea, that damaged two Russian navy vessels.