German submarines active on the Atlantic Ocean according to the U.S. Joint Intelligence Committee Daily summary dated 12 May 1942

An item reported that the number of enemy submarines moving to the west Atlantic Ocean exceeded with around six the submarines bound for the east. Recently attacked a submarine a freighter in the entrance to th St. Lawrence River, Canada.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 153 dated 12 May 1942