The detached U-boats were designated wolfpack 'Leopard', but were soon ordered to change course to close a larger convoy spotted by wolfpack 'Wolf' about 400 miles to the west. At 05:00 on 12 October, "U-353" spotted an independently sailing merchant ship of 4,000 to 5,000 tons, and closed to attack, firing two torpedoes from a range of 2,000 yards. The ship promptly altered course, and the U-boat fired another torpedo from her stern tube. Two loud explosions were heard, and the ship was seen to break in two and sink. "U-353" surfaced and closed at full speed, only to find "U-133" already there and claiming the victory. Eventually the two captains agreed that "U-353"s torpedoes had forced the ship to change course into "U-133"s line of fire, and they agreed to share the credit. Ten minutes later another U-boat was sighted, , which claimed to have sunk two ships. The U-boats then parted company to search for the convoy.