On the night of 31 May /1 June four midget submarines attempted entry to Sydney Harbour. The entry of unidentified objects was detected at the Loop Station but unreported. It is possible that one submarine that may have entered at the same time as a ferry. During the evening a number of torpedoes were fired resulting in the sinking of the Kuttabul. A week later on the 8th of June a submarine off the coast fired shells into Sydney Harbour many exploding in the streets of Rose Bay and Bellevue Hills with minimal damage though one left a crater in Manion Avenue, Rose Bay. Due to censorship restrictions little was known about these attacks until many years after the war.
The story of the Japanese submarines patrolling the New South Wales coast in 1942 is recorded by Stephen L Carruthers after researching records from Australian and Japanese resources and provides information about what was happening on the submarines as well as the effects of the attacks on Sydney.
Another book on this topic is Battle surface: Japan's submarine war against Australia 1942-44 by David Jenkins.