br br Ukrainian attack underwater drones struck a Russian submarine moored at the port of Novorossiysk in the Black Sea, according to information released by the Security Service of Ukraine (SSU).br br The operation reportedly employed submersible drones known as Sub Sea Baby, used in a joint action with the Ukrainian Navy.br br According to the SSU, the target was a Project 636.3 Varshavyanka-class submarine, known by NATO as the Kilo class. The explosion occurred near the stern of the vessel, where the horizontal and vertical rudders as well as the propeller are located. Ukrainian authorities stated that, as a result of the damage, the submarine suffered critical failures and was effectively rendered inoperable.br br The struck submarine was reportedly equipped with four Kalibr cruise missile launchers, a weapon system widely used by the Russian Navy for long-range strikes. The SSU added that the operation is part of a broader set of actions aimed at limiting Russian naval mobility in the Black Sea.