Operation Rimau

Operation Rimau was an attack on Japanese shipping in Singapore Harbour, carried out by an Allied commando unit Z Special Unit, during World War II using Australian built MKIII folboats. It was a follow-up to the successful Operation Jaywick, which had taken place in 1943, and Rimau, a shortened version of the word Harimau which is (Malay for tiger). It was again led by Lieutenant Colonel Ivan Lyon of the Gordon Highlanders. Originally named Operation Hornbill the aim of Rimau was to sink Japanese shipping by paddling the folboats in the dark and placing limpet mines on ships. It was originally intended that motorised semi-submersible canoes, known as Sleeping Beauties, would be used to gain access to the harbour, however, they resorted to folboats.

Thirteen men, including Lyon, were killed. The ten captured commandos were tried with 'perfidy and espionage' in a court and executed on 7 July 1945.

Operation
Lyon led a Z Special Unit contingent of twenty-one men. They left their base in Australia aboard the British submarine HMS Porpoise on 11 September 1944. When they reached the island of Merapas, which was to be their forward base, it was discovered to be inhabited. To ensure that their stores would remain undiscovered by the natives, one of the officers from the Porpoise, Lt Walter Carey, remained on Merapas as a guard.

The force commandeered a Malay junk named the Mustika. Taking the Malay crew aboard the submarine, Z Special Unit transferred their equipment to the junk and the Porpoise departed. Lyon decided to drop four more men with Carey off: Warrant Officer Alf Warren, Corporal Colin Craft and either Sergeant Colin Cameron or Lance Corporal Hugo Pace (accounts differ on the identity of the fourth man).

Meanwhile, the Mustika neared its target. On the day of the planned attack, 10 October 1944, disaster struck. A patrol boat challenged the Mustika and someone on board opened fire. Their cover blown, Lyon had no option but to abort the mission. After blowing up the junk and the Sleeping Beauties, he ordered his men to paddle back to Merapas by use of the folboats that they had stored on Mustika. However, Lyon led a small force of six other men — Lt Commander Donald "Davo" Davidson, Lt Bobby Ross, Able Seaman Andrew "Happy" Huston, Corporal Clair Stewart, Corporal Archie Campbell and Private Douglas Warne — into Singapore Harbour by folboat, where they are believed to have sunk three ships with limpet mines.

While the main party returned safely to Merapas, the raiding party did not fare so well. The Japanese caught up with Lyon and his party on Soreh Island. A gun battle ensued and Davidson and Campbell were severely wounded. Lyon, Ross and Stewart stayed on Soreh to hold off the Japanese in order for the wounded duo to escape. After a battle, Lyon and Ross were killed by a hand-grenade on 16 October 1944, Stewart was captured. Davidson and Campbell made it by folboat to Tapai Island where they died on 18 October, either from their wounds or by swallowing their suicide pills. The two remaining members of the raiding party, Huston and Warne, reached Merapas.

In all, ten members of the contingent were captured. They were brought to Singapore and held at Outram Road Prison. On 3 July 1945, they were put on trial for espionage, found guilty and executed. The ten men were beheaded on 7 July 1945—barely a month before the war came to an end. These ten men, Lyon and four others are buried at Kranji War Memorial.