At 00.45 hours on 14 October 1941 the unescorted and neutral Aingeru Guardakoa was torpedoed and sunk by U-204 off Cape Roche south of the Bay of Cadiz. As the U-boat was later lost during the patrol the circumstances of this attack are not clear, but it seems the Germans mistook her for a British submarine chaser. At least two torpedoes were fired of which one was seen passing astern by a survivor, who heard a buzz and saw bubbles but thought that it was a shoal of sardines. The ship sank immediately after being hit and the master and four crew members clung to debris until they were picked up the next morning by a fishing boat and taken to its home port Santa Uxía de Ribeira, Spain.