The Altmark incident (Norwegian: Altmark-affæren; German: Altmark-Zwischenfall) was a naval incident of World War II between British destroyers and the German tanker Altmark, which happened on 16–17 February 1940. It took place in what were, at that time, neutral Norwegian waters. On board the Altmark were roughly 300 Allied prisoners (officially internees), whose ships had been sunk by the pocket battleship Graf Spee in the Southern Atlantic Ocean. British naval forces cornered the tanker and later the destroyer HMS Cossack boarded the Altmark near the Jøssingfjord and liberated all the prisoners; eight German sailors were killed and ten wounded during the hand-to-hand fighting which took place during the boarding. A British sailor was also wounded during the fighting. The German government claimed that the boarding was a violation of international law and Norwegian neutrality, and later used the incident in the propaganda broadcasts of "Lord Haw-Haw". Background In February 1940, the German tanker was returning to Germany with 299 captured British sailors on board. These were prisoners of war who had been picked up from ships sunk by the pocket battleship . On its way from the southern Atlantic to Germany, the Altmark passed through Norwegian waters. International law did not ban the transfer of prisoners of war through neutral waters. On the insistence of British contacts who had been pursuing the vessel, it was investigated three times on 15 February by the Royal Norwegian Navy. First, the tanker was boarded by officers from the torpedo boat HNoMS Trygg, off Linesøya, then by officers from the torpedo boat HNoMS Snøgg in the Sognefjord, and finally personally by Admiral Carsten Tank-Nielsen and naval personnel from the destroyer HNoMS Garm in the Hjeltefjord. In each instance, the men who boarded the ship carried out cursory searches and took the Germans' word that the vessel was conducting purely commercial business. The British prisoners held in the ship's hold reportedly made strenuous efforts to signal their presence, but the Norwegian search parties did not inspect the hold, and allowed the ship to continue on its way. Following the third boarding, Altmark was escorted southwards by the torpedo boats HNoMS Skarv and HNoMS Kjell and the guard boat HNoMS Firern. Incident Altmark was then spotted off Egersund later that same day by British aircraft, which raised the alarm in the Royal Navy. The aircraft were stationed at RAF Thornaby, in the North East of England.