Ukraine says Friday's missile strike on the headquarters of Russia's Black Sea fleet in Crimea was timed to coincide with a meeting of naval officials, APA reports citing BBC.
In a short statement, the Ukrainian military claimed the strike had caused deaths and injuries but did not provide more details.
On Friday Moscow said one serviceman was missing after the attack.
The fleet, based in the port city of Sevastopol, is seen as the best of Russia's navy.
A Ukrainian military source told that Friday's attack was carried out using Storm Shadow missiles, which are supplied by Britain and France.
The Ukrainian military statement on Saturday asserted that it had left "dozens of dead and wounded occupiers, including the top management of the fleet".
Kyiv's intelligence chief, Kyrylo Budanov, claimed that two Russian commanders were badly injured in the missile strike.
The Sevastopol area came under renewed attack on Saturday. The city's Russian-installed governor, Mikhail Razvozhaev, said debris from a missile shot down by air defences had fallen near a pier.
He also told residents he was ordering an inspection of bomb shelters following some complaints they were hard to access or in poor condition.