Ukraine's military said on Aug. 3 that a Ukrainian missile strike the day before sunk a Russian Black Sea Fleet submarine and damaged a S-400 air defense system in Russian-occupied Crimea.
In a statement on Telegram, the military said that the Ukrainian strike had "significantly damaged" four launchers of Russia's modern S-400 Triumph air defense system.
The military named the Kilo-class submarine Rostov-on-Don as the submarine that it says sunk in the port of Sevastopol.
"As a result of the hit, the boat sank on the spot," the General Staff said in the statement.
The military said that the submarine, capable of launching Kalibr cruise missiles, had sustained "significant damage" in an earlier September Ukrainian missile attack but it had been repaired. The estimated value of the submarine is $300 million, according to the military.
The Kyiv Independent could not independently verify Ukraine's claims.
The Russian Defense Ministry has not reacted to Ukraine's claims over the reported strike.
A day before on Aug. 2, residents in Crimea reported hearing multiple blasts in Sevastopol, Simferopol, and Yevpatoria in the occupied peninsula, the Telegram channel Crimean Wind reported.
Mikhail Razvozhayev, the Russia-installed proxy head of Sevastopol, also claimed without evidence on Aug. 2 that fragments of drones and U.S.-made missiles were found in the city after being downed by air defenses.
Razvozhayev has not commented on Ukraine's Aug. 3 statement that it sunk the submarine or damaged the missile system.
The statement comes as Ukraine continues to target Russia's Black Sea Fleet and military targets in Crimea, illegally occupied by Russian troops since 2014.
Ukraine has repeatedly struck Russia's vessels since the beginning of the full-scale invasion, leaving around 30% of Russia’s Black Sea Fleet is lost or disabled, according to the Ukrainian military.
Successful Ukrainian strikes on occupied Crimea forced Moscow to pull out much of its naval forces from the peninsula to the Russian port city of Novorossiysk, which has become a key port for the Russian Black Sea Fleet.