Japanese aircraft carrier Kasuga Maru attacked by American submarine according to the U.S. Joint Intelligence Committee daily summary dated 4 May 1944

An item reported that an anonymous American submarine while patrolling in the Far East waters attacked the Japanese aircraft carrier of around 22.500 tons Kasuga Maru scoring two torpedo hits.(1) If she sunk was unknown. According to the Joint Intelligence Committee was she originally a fast cargo-passenger ships but prior to her completion rebuilt into an aircraft carrier. As a result she was not a converted carrier but a real aircraft carrier. Further more were 1-6.000 ton supply vessel. 1 cargo ship and the escorting destroyer by American submarines destroyed.

Note

1. Laid down by Mitsubishi Shipbuilding&Engineering, Nagasaki, Japan on 6 January 1940, launched on 19 September 1940, handed over to the Japanese Imperial Navy, completed at the Sasebo Naval Arsenal between 2-15 September 1941, renamed Taiyo on 3 August 1942 and sunk off Cape Bolinao, Luzon, Philippines on 18 August 1944 by the American submarine USS Rasher. A Taiyo-class escort carrier with a displacement of 18.116 (standard)-20.321 (normal) tons.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 145 dated 4 May 1942