Strong Japanese naval force bound for the Bay of Bengal according to the U.S. Joint Intelligence Committee. Daily summary dated 17 March 1942

 An item reported that the Japanese naval forces which seemed to participate in the advance of the Bay of Bengal consisted of 1 aircraft carrier, 3 cruisers, 8 destroyers, 4 converted seaplane tenders and around 75 shore-based aircraft.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 97 dated 17 March 1942.