"Sea Baby" marine drones were used in recent attacks on Russia's Black Sea Fleet patrol ship Pavel Derzhavin and cruise missile carrier Buyan, an unnamed source told the Ukrainian media outlet Hromadske on Oct. 13.
The unnamed source told Hromadske that Ukraine's Security Service (SBU) worked together with the navy to pull off the attacks.
Ukrainian navy spokesman Dmytro Pletenchuk told the Radio Free Europe/Radio Liberty on Oct. 12 that Pavel Derzhavin was damaged in an explosion, although he did not provide further details.
This is not the first time Sea Baby drones have been used to strike Russian military targets.
In July, Sea Baby drones were used by the SBU to strike the Kerch bridge.
In combination with sea drones, Ukrainian forces have used aerial drones, missiles, sabotage, and other methods to inflict significant damage on the fleet and Russian forces in occupied Crimea.
On Aug. 3, U.K. Armed Forces Minister James Heappey said that Ukrainian attacks on Russia's Black Sea Fleet have led to the "functional defeat" of the Russian Navy in the Black Sea.