In March 1941, to support the planned German invasion of the Balkans, Vice Admiral Angelo Iachino's Italian fleet, led by the battleship , sailed to intercept Allied convoys between Egypt and Greece. Warned of the Italian intentions by intelligence from the Government Code and Cypher School at Bletchley Park, Admiral Cunningham took his fleet to sea on 27 March 1941, flying his flag on "Warspite". On 28 March the British cruisers encountered the Italian fleet and were forced to turn away by the heavy guns of "Vittorio Veneto". To save his cruisers Cunningham ordered an air attack, prompting Iachino to retreat. Subsequent air attacks damaged the battleship and the cruiser , slowing the former and crippling the latter. "Vittorio Veneto" escaped to the west as dusk fell but the British pursued through the night, first detecting "Pola" on radar and then two of her sister ships. "Warspite", "Valiant" and "Barham" closed on the unsuspecting Italian ships and aided by searchlights, destroyed the heavy cruisers and and two destroyers at point blank range. "Pola" was also sunk once her crew had been taken off. Having established by aerial reconnaissance that the rest of the Italian fleet had escaped "Warspite" returned to Alexandria on 29 March, surviving air attacks without suffering casualties.