At 05.01 hours on 3 Jun, 1942, U-404 attacked the unescorted Anna with gunfire, after two torpedoes fired at 03.09 and 04.50 hours had missed. After 7 minutes the gun crew had to cease fire because they were blinded by a searchlight from the ship which then tried to communicate with the U-boat by blinking light. In the moonlight the Germans could see Swedish neutrality markings, but decided to continue the attack because the ship was sailing darkened and on zigzag courses. At 08.50 hours, three rounds were fired from close distance into a hold, the Anna caught fire and sank by the stern at 09.55 hours.