Ukraine’s military asserted on Monday that it had killed the commander of Russia’s Black Sea Fleet in a missile attack last week, which, if confirmed, would make the strike among the most damaging for the Russian Navy since the sinking of the fleet’s flagship last year. There was no immediate comment from Moscow’s Defense Ministry on the status of its fleet commander, Adm. Viktor Sokolov, who is one of the most senior figures in the Russian Navy. Ukraine’s claim could not be independently verified.

Ukraine’s special operations forces on Friday said they had struck a headquarters of the Russian fleet in the Crimean city of Sevastopol, a storied port that is now under regular bombardment from Ukraine’s long-range missiles and exploding drones. Fleet officers were holding a meeting there at the time, the Ukrainian military said.