The Ukrainian military has reportedly destroyed a Russian air defense system in Russian-annexed Crimea. Ukraine's forces appear to be stepping up their operations in the region.
The Russian defense ministry announced on Thursday that its air defenses shot down 11 drones over Crimea in southern Ukraine.
The Ukrainian military said on social media that it hit an enemy surface-to-air missile system in western Crimea.
Ukrainian media outlets have cited intelligence sources as saying that Ukraine used drones and Ukrainian-made Neptune anti-ship missiles in the attack.
In Crimea, Russia's advanced S-400 surface-to-air missile system was destroyed in August.
The Ukrainian military also said on Thursday that it damaged two Russian navy patrol ships in the Black Sea off Crimea.
The day before that, Ukrainian forces launched an attack on the Crimean port city of Sevastopol, which is where the Russian Navy's Black Sea Fleet is stationed.
Ukrainian military sources have told NHK that they used British-supplied cruise missiles and other weapons to damage a Russian landing ship and a submarine.