Three Japanese midget submarines were released from their mother submarines off the east coast of Australia and commenced an attack on Sydney Harbour. The alarm was raised when one of the midget submarines was caught in the boom net across the entrance to Sydney Harbour, but by that time the other two had slipped into the harbour. The crew of the submarine caught in the boom net subsequently committed suicide by blowing the submarine up. Harbour patrol craft commenced searches for the submarines and carried out attacks on them. One of the midget submarines was caught in Taylors Bay and depth charges were dropped on her. With no hope of escape her crew then committed suicide.
The third submarine conducted a torpedo attack against USS CHICAGO, (cruiser), but the torpedo missed and subsequently sank HMAS KUTTABUL, (depot ship), berthed at Garden Island. 21 RAN and RN sailors sleeping onboard KUTTABUL were killed. This third midget submarine is believed to have escaped from Sydney Harbour, but disappeared and never returned to her mother submarine.
HMAS CANBERRA, (cruiser), was fitted with A290 air warning radar Type 271 at Sydney’s Garden Island Dockyard. The equipment was on the secret list, and was fitted with explosive charges to ensure it did not fall into enemy hands.
The store-carrier HMAS BARALABA, was commissioned. BARABALA was laid down in Stettin, Germany, in 1921, and registered by the Australian United Steam Navigation Co Ltd in 1925. She was requisitioned for the RAN on 31 May 1942.