At 23.12 hours on 7 Jul, 1940, the unescorted and unarmed Bissen (Master E. Svensson) was hit ahead of amidships by one torpedo from U-99 about 80 miles south-southwest of Cape Clear, Ireland. The explosion threw parts of the deck cargo all over the ship, blew a raft overboard and caused the ship to settle quickly by the head. The crew immediately abandoned ship in two lifeboats and noticed too late that the second officer was still aboard. It was difficult to get back to the sinking Bissen as the engines were still running and the ship was steaming slowly in circles, but after several attempts the boat in charge of the master managed to rescue him. The U-boat had to leave the area shortly after the attack because a destroyer was sighted. The survivors were picked up about one hour later by the British destroyer and landed at Plymouth on 9 July.