In the evening of 9 April "Nordkapp" intercepted the 6,031-ton German tanker "Kattegat" of Bremen in the Glomfjorden south of Narvik. "Kattegat" was one of two naval tankers the Germans intended to use in order to quickly refuel the ten destroyers of the Narvik task force, enabling them to escape back to Germany before the Royal Navy could trap and sink them. In preparation of her supply mission, "Kattegat" had departed the pilot station at Kopervik in Western Norway on 6 April, scheduled to arrive at Narvik on 9 April. The "Kriegsmarine" support tanker had sailed to Norway from Wilhelmshaven on the German North Sea coast on 3 April in preparation for the invasion. While the other tanker, the 11,766-ton whale oil factory ship "Jan Wellem", had reached Narvik from the German Basis Nord at the Bolshaya Zapadnaya Litsa inlet on the Kola Peninsula in Russia before the German attack, the captain of "Kattegat" had been warned of a British naval mine field in the Vestfjorden (Operation Wilfred) and refused to continue, choosing instead to anchor up in Sandlågbukta, Neverdal at Ørnes in Meløy.