Fearing detection, the Japanese force subsequently returned to the Netherlands East Indies (NEI), arriving on 16 March.

The appearance of a powerful Japanese naval force at Singapore concerned the Allies, as it was feared that these ships could potentially conduct raids in the Indian Ocean and against Western Australia.

[1] In response, the Allies strengthened their naval and air forces in the area by transferring two British light cruisers from the Atlantic and Mediterranean as well as several U.S. Navy warships from the Pacific.

The Admiralty rejected this request, and directed that the fleet should remain at Trincomalee unless it was threatened by a superior Japanese force as its withdrawal would affect morale and harm Britain's prestige in the region.

[3] In late February, Vice-Admiral Shiro Takasu—the Commander in Chief, Southwest Area Fleet—ordered the heavy cruisers Aoba, Chikuma, and Tone to raid Allied shipping on the main route between Aden and Fremantle.

In his instructions to Sakonju, Vice Admiral Takasu directed that if the force captured Allied merchant seamen all prisoners, other than radio operators and other personnel who might possess useful information, were to be killed.

The raiders were supported by 10 medium bombers and three or four seaplanes based in Sumatra and west Java which conducted patrols in the direction of Ceylon.

[7] After leaving the Sunda Strait, the Japanese heavy cruisers sailed south-west for the main route between Aden and Fremantle.

[3] The ship was travelling from Fremantle to Bombay as part of a voyage between Newcastle, New South Wales and the United Kingdom carrying a cargo of zinc.

[12] Following the attack, Sakonju judged that it was too dangerous to continue the raid as Behar's distress message may have alerted the Allies to his force's presence.

[13] The heavy cruisers were again escorted through the Sunda Strait by Kinu, Ōi and five destroyers, and arrived back at the NEI on 15 March.

[3][5] During this time, the Behar survivors were held in a small and extremely hot store room on board Tone, and were given little access to food and water, sanitary facilities and exercise.

In the meantime, Somerville had decided on 16 March that surface raiders no longer posed a threat to shipping in the Indian Ocean and allowed Allied vessels to resume their normal routing.

[7] Shortly after the Behar survivors were rescued, Sakonju sent a radio message to Tone's commanding officer, Captain Haruo Mayuzumi, reprimanding him for taking non-essential personnel prisoner and not capturing the merchant ship.

The Japanese made no attempt to capitalize on their numerical superiority in the region and by the end of the month it had vanished; reinforcements to the Eastern Fleet enabled Somerville to start a series of carrier raids, commencing with an attack on Sabang on 19 April 1944.

When the British Government negotiated gratuities for Far East Prisoners of War the Foreign and Commonwealth Office disavowed knowledge of her captivity.

Vice Admiral Takasu had died from disease in September 1944, but Sakonju was tried by the British in 1947 at Hong Kong and sentenced to death and executed 21 January 1948.