Russia's Black Sea Fleet Command uses civilian ships to cover the military, reported by the Naval Forces of the Armed Forces.
"The leadership of the russian Black Sea Fleet has begun to use the insidious russian “tactics" known since 2014, but now at sea," the statement said.
War criminals pull to Sevastopol port merchant navy vessels with AIS identification systems turned off to make it impossible to identify them as civilian vessels.
"Hiding their warships behind those vessels, the occupiers continue to destroy peaceful Ukrainian cities and kill our citizens with Kalibr cruise missiles," the Navy added.
The director of the Ukrainian Institute of Maritime Law and Security, Bohdan Ustymenko, said that russia was actually holding captive 84 seagoing vessels carrying about 450 sailors.