Enemy submarines destroyed in vicinity of Columbia river, USA according to the U.S. Joint Intelligence Committee. Daily summary dated 25 December 1941

An item reported that in the morning of 24 December an US Army bomber attacked and undoubtedly destroyed with a direct hit an enemy submarine 50 miles off the Columbia river.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 15 dated 25 December 1941.