During World War II, Z Special Unit launched a raid on which of these four harbours?

Z (“zed”) Special Unit was a joint Allied specialist reconnaissance and sabotage unit formed during the Second World War to operate behind Japanese lines in Southeast Asia.

In early 1943 Captain Ivan Lyon (British) and Bill Reynolds (Australian), formed a plan for the Unit to attack Japanese shipping in Singapore Harbour using a vessel disguised as a fishing boat. On 2 September 1943 the plan was launched. “Krait” -- a converted Japanese coastal fish carrier (pictured) -- departed Australia for Singapore with Lyon and 13 other Z Special Unit members aboard, arriving off Singapore on 24 September. Six men left “Krait” and paddled 50 kilometres (31 mi) with collapsible canoes to establish a forward base in a cave on a small island near the harbour. On the night of 26 September 1943, they paddled into the harbour and placed limpet mines on several Japanese ships. The mines sank or seriously damaged six or seven Japanese ships, comprising over 39,000 tons between them. The commandos waited until the commotion over the attack had subsided and then returned to “Krait” by 2 October.

Z Special Unit carried out a total of 80 other operations in the southwest Pacific theatre. Although it was disbanded after the war, many of the training techniques and operational procedures employed were later used during the formation of other Australian Army special forces units and they have remained a model for guerrilla operations.