At 23.04 hours on 1 June 1940 the unescorted Ioanna (Master Vasilis Laskos), a straggler from convoy HG-32F since the night of 29/30 May, was stopped by three shots across her bow by U-37 about 120 miles west of Cape Finisterre. At 22.25 hours, the U-boat had fired a G7a torpedo that was a circle runner. The crew immediately abandoned ship and were questioned by the Germans. The master told them that he was a former Greek submarine commander and he left the papers behind because it was clear for him that his ship would be sunk. He also offered the Germans the provisions that could be found on board, but the U-boat left after firing one G7a torpedo as coup de grâce at 23.04 hours, which struck the drifting Ioanna on starboard side and caused her to sink after 10 minutes. The survivors later landed at Vigo.