Allied submarine attacked successful Japanese convoy in the Bay of Bengal according to the U.S. Joint Intelligence Committee. Daily summary dated 17 August 1942

An item reported that on 2 August an Allied submarine attacked in the Bay of Bengal an enemy merchant cruiser escorting 4 ships northward coming from the direction of Penang, Malaysia. Three ships were attacked, probably two were destroyed by the torpedoes.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 250 dated 17 August 1942.