'Source' (ii) was the Allied naval response to the German 'Sizilien' (17/23 October 1943).

On this date the US heavy cruiser Tuscaloosa, escorted by the US destroyer Fitch and three British destroyers, landed Free Norwegian troops on Spitsbergen island, to the north of German-occupied Norway, to re-establish the bases destroyed in 'Sizilien'.

In the summer of 1943 Tuscaloosa had departed Boston, Massachusetts, and escorted the British large troopship Queen Elizabeth to Halifax, Nova Scotia, before rendezvousing with the US aircraft carrier Ranger and proceeding across the Atlantic Ocean to Scapa Flow in the Orkney islands group to resume operations with the British Home Fleet. Tuscaloosa undertook sorties into the North Sea, in company with British and US ships, in unavailing efforts to lure German heavy warships to sea. On 2 October, Tuscaloosa was part of the covering force for Ranger in 'Leader' as the carrier launched air strikes against port installations and German shipping at the port of Bodø in German-occupied Norway. These were the first US naval air attacks against a European targets, and lasted from 2 to 6 October. Luftwaffe warplanes attempted to attack Ranger's attack aircraft, but were beaten off by US fighters.

Shortly after the end of 'Leader', the Germans did undertake a surface warship foray in the form of 'Sizilien' aimed at the important Allied weather station on Spitsbergen island. Tirpitz and other heavy warships shelled the installation and its garrison before retiring, unscathed, to northern Norway.

Tuscaloosa then took part in the 'Source' (ii) relief expedition to re-establish the station before the onset of winter. Assigned to Force 1, the cruiser loaded two LCV(P) small landing craft and cargo and departed the Seyðisfjörður in eastern Iceland in company with one US and three British destroyers on 17 October. Providing cover was Force 1 comprising the British battleship Anson, British heavy cruiser Norfolk, carrier Ranger, Canadian destroyers Haida and Iroquois and British destroyers Hardy, Janus and Vigilant within the 'Gearbox III' and 'FQ' undertakings.

On the morning of 19 October, Force 1 arrived off devastated Barentsburg and immediately started unloading operations. While the presence of floating ice hampered anti-submarine screening by the destroyers' sonar, Tuscaloosa landed a party of 160 men to help unload the supplies and equipment required for the re-establishment of the meteorological station. By the fall of darkness the cargo had been unloaded, and the ships of Force 1 departed the area. After refuelling at Seyðisfjörður, the cruiser proceeded to the Clyde river to disembark the survivors of the original Spitsbergen garrison.