Of the 12 men, three were killed, seven were captured, and two returned to their lines.[8] Soviet EPRON Diver K.D. Zolotovskiy claims his Soviet frogman team had underwater skirmishes with German frogmen in the Svir river.[9] 1944 December: German frogman operations in the Vistula river. After Italy changed sides, the German frogman unit MEK71 based in Jugoslavia made numerous attacks against liberated Italy, using two-man canoes.