https://en.defence-ua.com/news/ukra...from_the_baltic_to_the_caspian_sea-16034.html
At 04:31 in the morning on October 4, 2025, Ukraine's Special Operations Forces carried out a successful strike against russian Grad small missile ship (hull number 575), a Project 21631 Buyan-M corvette. The attack took place on Onega Lake, in the Republic of Karelia, deep inside russian territory.
The hit landed on the starboard side of the ship's engine compartment, inflicting significant damage.
The Grad ship was on its way from the Baltic Sea to the Caspian Sea
(going down Volga River) when it was struck. This route indicates that the russian Navy was likely transferring the vessel to another operational zone, possibly in preparation for new missions or reallocation of forces. The timing and precision of Ukrainian operation demonstrate careful planning and the growing reach of Ukrainian special units.
Couldn't find any footage, think it's on Fbook...