 On 14 December 1941 the unescorted and neutral "Cassequel" was hit in the stern by one of two torpedoes from U-boat-108 about 160 miles southwest of Cape St. Vincent, Portugal, and sank immediately.The "Serpa Pinto" was also stopped and boarded in 1944 (26 May) in the mid-Atlantic by the German submarine "U-541", but the ship was ultimately allowed to proceed after the German naval authorities declined to approve its sinking.On 5 June 1944, just before the Normandy invasion, following the threats of economic sanctions by the Allies, the Portuguese government opted for a complete embargo on wolfram exports to both the Allies and the Axis, thereby putting 100,000 Portuguese labourers out of work.