A Russian warship sank off the Crimea peninsula after Ukrainian underwater drones attacked it, Ukrainian officials said on Tuesday.
The Ukrainian military intelligence service HUR announced the hit on Telegram.
It said the ship had suffered hits to the stern, port and starboard sides.
The sinking was at least unofficially confirmed in Moscow.
The pro-Russian military blog Belorussky Silovik reported that the ship had been destroyed.
The influential blog Rybar, which is close to the Moscow Ministry of Defence, had a similar post.
The Crimean Bridge, also known as the Kerch Strait Bridge, was also closed for hours after drone attacks during the night.
The Sergei Kotov, which is a small warship known as a corvette, was part of Russia’s Black Sea Fleet.
It was deployed as a heavy patrol boat.
A video circulating was said to have shown the hit on the boat during the night.
It was believed to show a ship in the bay of Feodosia in south-east Crimea firing at targets in the water, until it itself was rocked by a heavy explosion.
Last autumn, there were reports of a drone fire on the same boat, which reportedly suffered severe damage.
The Russian Black Sea Fleet has a total of four such patrol boats.
They are among the most modern ships in the squadron and were only launched in 2017.
Powered by German diesel engines, the corvettes can also fire modern Kalibr cruise missiles, which the Russian fleet has also used to attack Ukrainian ground targets far inland.
The boats targeted Ukraine’s energy supply and other targets.
(dpa/NAN)