The Italian Navy's most successful attack, however, was when human torpedo divers planted mines on British battleships in Alexandria (Egypt) harbour (19 December 1941), and the HMS "Queen Elizabeth" and HMS "Valiant" were sunk . After these sinkings (and the contemporary destruction of the British "Force K"), the Italian Navy obtained for some months the nearly complete control of the central Mediterranean. In this way the Regia Marina was able to deliver the military supply and oil for the "Axis" victory of Tobruk and for the advance toward El Alamein in Egypt.