Several enemy submarines active on the Atlantic Ocean according to the U.S. Joint Intelligence Committee Daily summary dated 10 May 1942

An item reported that a coast guard vessel destroyed an enemy submarine south of Cape Lookout [North Carolina, USA] and rescued some of her crew members. It was estimated that there were 34 submarines of the enemy active on the Atlantic Ocean west of of the Azores. Sixteen east or west bound in equal numbers. 9 probably stationed of the North American coastline north of Charleston, South Carolina and another 9 south in the Gulf of Mexico, 2 in the Key West-Bahamas area, 4 in the Caribbean, 1 off the Guianas and perhaps one off Northern Brazil.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 151 dated 10 May 1942