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In April 1942 General Sir Thomas Blamey, Commander in Chief of the Australian Military Forces (AMF or the Australian Army) and C in C of the Allied Land Forces, instructed Lieutenant Colonel GE Mott (former head of SOE in Java) to set up Special Operations in Australia, under the cover name of the Inter-Allied Services Department (ISD). The ISD later came under the control of General MacArthur's General Headquarters (GHQ) for the South West Pacific Area (SWPA), rather than Blamey's Land Headquarters (LHQ), which controlled those Australian Army forces not allocated to MacArthur.

The ISD was established by June 1942, and training facilities were required for operations. As security and climactic conditions were not suitable at the Guerrilla Warfare School at Foster, Victoria, a new school was established at Z Experimental Station (ZES) in Cairns. Most personnel were recruited (volunteers) from the AMF and in June 1942 a holding unit for army personnel within the ISD was created for administration purposes: 'Z' Special Unit. This unit held a unique position within the Australian Army; it was paid and controlled by the ISD, had no war establishment, and had 'cart blanche' authority to draw from Ordnance.

On 6 July 1942 the Allied Intelligence Bureau (AIB) was established, to report on the enemy in the SWPA outside Australia, and also to weaken the enemy by sabotage and aiding local resistance groups. The ISD became Section 'A' of the AIB, while Secret Intelligence Australia (SIA) was Section 'B'; the Combined Field Intelligence (coast watching) Section was Section 'C'; and the Military Propaganda Section was Section 'D'. However, friction between the ISD and the AIB over funding, role and control eventually led to ISD being liquidated and Mott being relieved of duty in February 1943. In April 1943 a new organisation was created, Special Operations Australia. To avoid confusion between the names of the SOA and the SOE, from May 1943 the cover name Services Reconnaissance Department (SRD) was used.


The SRD was basically autonomous from the AIB, and as 'Z' Special Unit remained with the SRD, a similar holding unit, 'M' Special Unit, had to be created for the AIB. The strength of 'Z' Special Unit (for Australian Army SRD personnel only, with personnel from the other services and the United Kingdom being detached to the SRD from other war establishments) was governed by a ceiling by ranks, rather than a set war establishment. In May 1944 this ceiling was 91 officers and 447 ORs; and by July 1945 it was 205 Officers and 996 ORs. This ceiling allowed specialists to be assigned to the unit as necessary, without the paperwork of changing a war establishment.



Z Special Unit was a joint Allied special forces unit formed during the Second World War to operate behind Japanese lines in South East Asia. Predominantly Australian, Z Special Unit was a specialist reconnaissance and sabotage unit that included British, Dutch, New Zealand, Timorese and Indonesian members, predominantly operating on Borneo and the islands of the former Netherlands East Indies.

The unit carried out a total of 81 covert operations in the South West Pacific theatre, with parties inserted by parachute or submarine to provide intelligence and conduct guerrilla warfare. The best known of these missions were Operation Jaywick and Operation Rimau, both of which involved raids on Japanese shipping in Singapore Harbour.




In 1943, a 28-year-old British officer, Captain Ivan Lyon (of the Allied Intelligence Bureau and Gordon Highlanders), and a 61-year-old Australian civilian, Bill Reynolds, devised a plan to attack Japanese shipping in Singapore Harbour. Commandos would travel to the harbour in a vessel disguised as an Asian fishing boat. They would then use folboats (collapsible canoes) to attach limpet mines to Japanese ships. Reynolds was in possession of a 21.3-metre (70 ft) Japanese coastal fishing boat, the Kofuku Maru, which he had used to evacuate refugees from Singapore. Lyon ordered that the boat be shipped from India to Australia. Upon its arrival, he renamed the vessel MV Krait, after the small but deadly Asian snake. The Krait travelled from a training camp at Broken Bay, New South Wales to Thursday Island. Aboard was a complement from Z Special Unit of three British and eleven Australian personnel.

On 13 August 1943, the Krait left Thursday Island for Exmouth Gulf, Western Australia, where it was refuelled and repairs were undertaken. Not only did the repairs cause delays in departure, but the folboats which had been specially ordered for the attack by Lyon from England only arrived at the last minute. They were found to be faulty, lacked some important parts and were not according to the design that Davidson had specified. They had to undergo many on the spot changes simply to make each framework fit together and then fit correctly into the outer skins. This left the crew little time to get accustomed to them before being loaded on to the Krait. [1][2][3]

On 2 September 1943, the Krait left Exmouth Gulf and departed for Singapore. The team's safety depended on maintaining the disguise of a local fishing boat. The men stained their skin brown with dye to appear more Asiatic and were meticulous in what sort of rubbish they threw overboard, lest a trail of European garbage arouse suspicion. After a relatively uneventful voyage, the Krait arrived off Singapore on September 24. That night, six men left the boat and paddled 50 kilometres (31 mi) with folboats (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 before returning to their hiding spot.

In the resulting explosions, the limpet mines sank or seriously damaged seven Japanese ships, comprising over 39,000 tons between them.[4] The commandos waited until the commotion over the attack had subsided and then returned to the Krait, which they reached on 2 October. Their return to Australia was mostly uneventful, except for a tense incident in the Lombok Strait when the ship was closely approached by a Japanese patrol boat; however the Krait was not challenged. On October 19, the ship and crew arrived safely back at Exmouth Gulf.

The raid took the Japanese authorities in Singapore completely by surprise. Never suspecting such an attack could be mounted from Australia, they assumed it had been carried out by local saboteurs, most likely pro-Communist Chinese guerrillas. In their efforts to uncover the perpetrators, a wave of arrests, torture and executions began. Local Chinese and Malays, as well as interned POWs and European civilians were targeted in this programme. The incident became known as the Double Tenth, for 10 October, the day that Japanese secret police began the mass arrests.



After the success of the earlier Operation Jaywick mission in September 1943, Ivan Lyon started preparing for Operation Rimau. The plan was to deliver commandoes to enemy waters via submarine with 15 one-man, motorised submersible canoes known as "Sleeping Beauties" (SBs) (these could be used on the surface or travel semi-submerged, with the operator’s head above the water or fully submerged similar to a small submarine, the operator using artificial breathing apparatus similar to modern Scuba diving equipment); travel to the uninhabited Merapas Island in Indonesia which they would use as a base and place enough supplies for three months and have the commandoes capture a small local fishing boat. Sail the boat towards Singapore Harbour undetected, disguising the commandos as locals and reach the Bay of Kepala Jernih (in the Tambelan Archipelago) late on 9 October 1944 for 24 hours to allow an officer to carry out a reconnaissance from Pulau Subar ("Sisters' Islands"). The officer was to spend the time observing targets and later rendezvous with the junk to participate in the attack and two canoes would travel north to the vicinity of Labon Island to secure a hide for the junk and for another canoe to proceed to Subar. After darkness, the crew was to move the junk to an attack base at Labon using the "Sleeping Beauties", the party was to attach limpet mines to Japanese ships, sink thirty of them, damage another thirty, and escape to their base on Merapas Island by paddling their way back in two-man folboats (collapsible canoes), seventy miles to the east of Singapore. Then return to a rendezvous with the submarine on 7/8 November 1944 at Merapas Island; if the submarine failed to make contact with them it would stay in the area, returning to the designated point every night until 8 December 1944.

On the afternoon 28 September 1944 the Porpoise stopped a junk from Ketapang named the Mustika off the west coast of Borneo near Pontianak. Seven commandoes of boarded the boat and nine Malay crew were taken aboard the submarine. Twelve minutes later, Porpoise submerged with both vessels making their way back west towards a forward operational base at Pedjantan Island.
Over the next two nights, 29–30 September 1944, the Rimau commandoes, the SBs, folboats and other stores were transferred from Porpoise to Mustika.

Mustika returned via the Java Sea and Karimata Straits to Merapas Island. The Rimau Commandos disguised themselves as Malays by wearing sarongs and dyeing their skin. The Mustika had no engine though so the commandoes were dependent on winds.The Mustika arrived at Merapas on 4 October 1944. It appears Lyon decided to divide the party into two groups: 19 commandoes to take part in the raid, while four men would be left behind. These were meant to be Carey, Warren, Craft and Cameron or Pace. The Mustika then headed towards Singapore Harbour, reaching the vicinity of the harbour on or around 6 October 1944. It was thought to have been off the west coast of Pulau Batam. Pulau Laban is located at a distance of 11 miles from Keppel Harbour and was the intended forward point from which the attack was to be launched.

On 10 October 1944, two hours before sunset and an hour before the raid was to commence, disaster struck. A coastal Malay Police patrol boat, the Hei Ho, challenged the Mustika near Kasoe Island and Samboe Island. (The Japanese had increased surveillance of the area since Operation Jaywick.) It is unclear why the patrol boat approached the Mustika – various theories offered included: the ship flew the wrong flag; it was a suspicious size; the sailors were identified as white men, and not Malays.

Shots were fired between the vessels – it was later deduced one of the Australian commandos aboard panicked and started firing at the approaching patrol boat. Some of the patrol boat crew were killed but at least one escaped and managed to get back to report the incident. Lyon knew the patrol boat would seek help from Japanese occupation authorities and decided to abort the mission. He scuttled up the junk and the Sleeping Beauties (which were top secret weapons at the time) with explosive charges. He ordered his men to divide into four groups and make their way back to Merapas by use of the folboats that they had stored on Mustika. The groups were led by Lyon, Davidson, Page and Ross, respectively.

Three of the groups headed to Merapas immediately. Lyon led his group into Singapore Harbour. It consisted of himself and a small force of six other men — Lieutenant Commander Donald "Davo" Davidson, Lieutenant Bobby Ross, Able Seaman Andrew "Happy" Huston, Corporal Clair Stewart, Corporal Archie Campbell and Private Douglas Warne.They are believed to have sunk three ships with limpet mines, although evidence confirming this is limited. The Singapore Garrison of the Imperial Japanese Army did unleash a punitive force of at least 100 soldiers led by Major Hajime Fujita including army, navy and native police to find the commandoes.

On 15 October, five of the men (Lyon, Davidson, Ross, Stewart and Campbell) were on Soreah Island, or Pulau Asore, a small island just off Pulau Mapur, near Pankgil Island. A Japanese patrol caught up with them and arrived at the island at about 1400 hours and a gun battle ensued. The Australians withdrew to the western end of the northern beach, having selected two defensive positions in an unexposed area. The Australians ambushed the Japanese and their native auxiliaries. A gun battle ensued. 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. Lyon, Ross and Stewart held off 80–90 opposing soldiers forcing them to fight for 9 hours and inflicting heavy casualties. Lyon and Ross had climbed trees for an elevated firing position, and remained unseen until muzzle flashes betrayed their positions and they were killed by grenades. Stewart remained at large, but his folboat was taken and he was found days later on a subsequent sweep of the island.

The wounded Davidson and Campbell made it by folboat to Tapai Island on 16 October 1944. Both men died there, either from their wounds or committing suicide by cyanide capsule. On 4 November eighteen of the group were together on Merapas Island. A small Japanese force landed on the island, and was attacked by the commandos. Two of the Rimau commandos – Riggs and Sergeant Colin Cameron – were killed in combat on the island, while the remainder now split into two groups and went to different islands.

Australian forces intercepted a Japanese coded message reporting activity by about twenty commandos in the attack area. However, if the Australians had responded, it would have shown that the Allies had broken the Japanese secret codes. So the appointed rescue submarine was not told of the sudden urgency of the situation. The orders to the commander of the rescue submarine, HMS Tantalus, Lieutenant Commander Hugh Mackenzie, were to go to the rescue rendezvous area of Merapas Island on 7 November 1944, and to remain there until 7 December 1944 if necessary.

On 7 November 1944 ten of the Rimau commandos were in place to meet the rescue submarine but it did not appear, as Mackenzie had instead chosen to hunt for enemy shipping in the area. He made this decision in consultation with Major Chapman, Z Special Unit's contact on the submarine. Tantalus's main objective was offensive action against the Japanese and the orders to the Rimau party were that they might expect to be picked up at any time within a month of the initial rendezvous date.

On 21 November 1944 the submarine reached Merapas Island. Chapman and another commando, Corporal Croton, were worried about the surf and tracked their landing canoe around the island to calmer waters, away from the set position at 0200. Chapman wanted to head back to the submarine but Croton drew his pistol and forced Chapman on.

Croton and Chapman arrived at the designated meeting point after dawn on 22 November 1944. They found some evidence of the commandos having been there – the beginnings of a large lean-to shelter in a clearing at the top of a hill, away from the original base site; empty rations tins; half-cooked food on 'Commando Cookers'; fires seemingly kicked out; a few pieces of silver foil; empty cigarette cartons. They did not question local people about what happened.

Croton and Chapman returned to the submarine. Chapman and Mackenzie agreed that the operation had likely been a failure and that no purpose could be served in returning to Merapas, contrary to what had been planned. Tantalus resumed its patrol and arrived back in Fremantle on 6 December 1944 having never returned to Merapas Island. None of the officials in Australia who knew that the Rimau commandos were in trouble tried to contact the submarine and order them to remain in the area for any survivors.

Once the 7 December 1944 final deadline passed, the survivors realised that they would not be rescued. They attempted to make their way home the 3,000-kilometre distance to Australia. Over two weeks all the men were either captured, killed in firefights or drowned. Two men, Willersdorf and Pace were captured on 17 January 1945 on Romang Island, Indonesia, some 350–400 miles from Australia after a journey of approximately 2,000 miles by folbot. Willersdorf died of his wounds in Japanese captivity in Dili, East Timor in March 1945. Pace died of starvation several months later in June 1945 in the same facility. Both were buried on a hill approximately 200 metres from the prison facility. Warne was able to evade Japanese patrols until March 1945 but was captured after a bout of delirium brought on by fever. He was taken to Surabaya under the control of the Naval Police and interrogated so brutally he died of untreated wounds one month later.

In all, eleven members of the contingent were captured and brought to Outram Road Prison in Singapore. One commando, Marsh, died of malaria. During the imprisonment the men were tortured and provided starvation rations similar to those provided to other prisoners in the facility. On 3 July 1945, they were put on trial for perfidy and espionage. They were found guilty and sentenced to death. Official Japanese records state that the ten men were beheaded at Passir Panjang on 7 July 1945, approximately one month before World War II in the Pacific came to an end. Later evidence stated it took guards more than half an hour to execute the men, sometimes requiring two or three blows to complete beheading.



M Special Unit, was a joint Allied special reconnaissance unit, part of the Services Reconnaissance Department, in the South West Pacific theatre of World War II. A joint Australian, New Zealand, Dutch and British military intelligence unit, it saw action in New Guinea and the Solomon Islands between 1943–1945, against the Empire of Japan.

The unit was formed in 1943, as a successor to The Coastwatchers. Hence M Special Unit's role was focused upon gathering intelligence on Japanese shipping and troop movements. Small teams from the unit were landed behind enemy lines by sea, air or land, in contrast to its counterpart, Z Special Unit ("Z Force"), which became well known for its direct-action commando-style raids. M Special Unit on the other hand operated behind enemy lines for extended periods of times to collect intelligence undetected and as such rarely tried to engage the enemy.

After training on Fraser Island in 1943, M Special soon deployed where they operated in both the Solomon Islands and New Guinea conducting intelligence operations against the Japanese. The late 1943 the unit was split into smaller units code named ‘Whiting’ and ‘Locust’ where both units continued to collect intelligence. Generally, a very successful unit the consequences for those captured by the enemy were serve as demonstrated by the most infamous member of “M” Special Unit Sergeant Leonard Siffleet who was executed by Japanese forces via beheading.

When the war was won in late 1945, “M” Special Unit was disbanded.

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