USS Tunny made contact with a Japanese fleet off Truk, Caroline Islands at 2228 hours. She fired four torpedoes at the fleet, which now she realized was an aircraft carrier force, observing multiple hits. She then fired an additional six torpedoes before diving; the subsequent depth charge counterattack caused little damage. Later study of Japanese records revealed that the attacks caused only minor damage on the Japanese force as the torpedoes were detonated prematurely.