Secret agents, submarines and intelligence missions into the Japanese-occupied Netherlands East Indies
Among the most dangerous activities undertaken by the Netherlands Forces Intelligence Service (NEFIS) from Australia during the Second World War were clandestine missions into the Japanese-occupied Netherlands East Indies.
Small parties of Dutch and Indonesian agents were trained in Australia and inserted into enemy-held territory by submarine, aircraft or small craft. Their objectives included gathering intelligence, establishing wireless communications, contacting local populations and determining Japanese military strength and movements.
Within NEFIS, these activities became particularly associated with its special-operations component, commonly referred to as NEFIS III.
Its story, however, did not begin with NEFIS.
During 1942 and early 1943, Dutch and Indonesian personnel had already participated in clandestine operations through the Netherlands East Indies Section of Australia’s Inter-Allied Services Department (IASD). That earlier organisation and its often costly missions are examined separately in this Research Portal.
NEFIS III represented the next stage: greater Dutch control over the planning, training and conduct of clandestine intelligence operations directed towards the occupied NEI.
From the NEI Section to NEFIS
The Japanese conquest of the Netherlands East Indies in early 1942 left Dutch authorities in Australia with little direct information about conditions across much of the occupied archipelago.
The Allies faced the same intelligence problem.
Early attempts to penetrate the NEI were therefore undertaken through Australian-led intelligence and special-operations organisations. Dutch, Australian and Indonesian personnel worked together in the NEI Section of IASD, undertaking or planning missions to Java, Ceram, the Aru Islands, Celebes and other areas.
The results were sobering.
Some parties disappeared. Others were captured or betrayed. Several agents were executed. Communications were unreliable, transport was difficult to obtain and assumptions made in Australia about local conditions often proved wrong once agents reached occupied territory.
At the same time, disagreements emerged about control.
Dutch authorities regarded intelligence concerning the Netherlands East Indies as primarily a Dutch responsibility. Australian organisations had their own operational requirements and command structures.
The reorganisation of this system during 1943 increasingly transferred responsibility for NEI intelligence operations to NEFIS.
The Australian wartime record therefore shows continuity of personnel and operational experience, but an important organisational change.
Early missions such as FLOUNDER, TIGER and WALNUT should not simply be labelled “NEFIS III operations” when they originated under the earlier NEI Section structure.
The special-operations role
NEFIS III was intended to restore direct intelligence links with territories from which conventional Dutch intelligence networks had largely disappeared.
Its parties could be assigned several related tasks.
They might reconnoitre Japanese airfields, ports, troop concentrations and shipping; establish wireless contact with Australia; identify potential landing areas; obtain information about local political and economic conditions; locate Allied personnel; or establish contacts capable of providing continuing intelligence.
Some missions were also intended to prepare networks that could become useful as Allied forces approached.
This meant that NEFIS III operated at the boundary between intelligence collection and special operations.
The principal objective was generally information rather than combat. Agents were not conventional commando forces intended to attack large Japanese formations.
Survival depended upon secrecy.
Dutch and Indonesian personnel
Although NEFIS was a Dutch organisation, its clandestine operations depended heavily upon personnel from the Netherlands East Indies.
Indonesian agents brought languages, knowledge of local customs and communities, familiarity with terrain and, in some cases, personal connections in the areas where parties were expected to operate.
Dutch personnel could bring military, naval, intelligence, communications and administrative expertise, but Europeans were often much more conspicuous inside Japanese-occupied territory.
Mixed parties therefore became an important feature of operations.
This Indonesian contribution should not be regarded as peripheral to the NEFIS III story. It was fundamental to the attempt to operate secretly across a culturally and geographically diverse archipelago.
At the same time, these operations took place within the colonial structures of the Netherlands East Indies. Dutch officers generally occupied command positions, while Indonesians served within Dutch military and administrative organisations.
That relationship would become increasingly significant as Indonesian nationalism strengthened towards the end of the war.
Training in Australia
Sending agents into occupied territory required skills very different from conventional military service.
Personnel needed to operate in small groups, often without immediate support. They required training in wireless communications, intelligence gathering, fieldcraft, weapons, survival and clandestine procedures.
One of the principal Australian facilities associated with this work was the Z Experimental Station at Fairview House near Cairns.
Dutch and Indonesian personnel had trained there during the earlier IASD period. Following the intelligence reorganisation of 1943, the station became increasingly associated with NEFIS special operations.
Cairns was well placed geographically for operations moving north towards New Guinea and the eastern Netherlands East Indies.
The DACC Research Portal examines Z Experimental Station and its Dutch and Indonesian involvement in a separate article.
The communications lifeline
Wireless communications were central to the concept of clandestine intelligence operations.
An agent could obtain valuable information, but it was of little immediate military value if it could not be transmitted back to headquarters.
Parties therefore frequently included a trained wireless operator carrying portable radio equipment, batteries, codes and schedules for establishing contact with Australia.
Maintaining that link could be extraordinarily difficult.
Equipment could be damaged during landing. Batteries deteriorated in tropical conditions. Radio transmissions risked revealing the party’s location, while Japanese forces could attempt to capture equipment and use it for deception.
The loss of communications could also leave headquarters uncertain whether a party was still operating, had moved, had been captured or had been killed.
Reliable radio contact was therefore both the lifeline and one of the vulnerabilities of clandestine operations.
Getting agents into occupied territory
Transport presented another major problem.
The distances involved were enormous and most potential landing areas were controlled or patrolled by Japan.
Submarines offered one method.
Dutch, American and other Allied submarines could approach enemy-held coastlines at night and put small parties ashore, sometimes using collapsible boats or other small craft.
Flying boats provided another option as Allied air operations moved closer to the NEI.
Dutch naval aviation became particularly important in supporting later intelligence missions. Catalinas could operate over long distances and land on relatively sheltered coastal waters.
But insertion was only the beginning.
A successful landing could quickly turn into disaster if local conditions had changed, Japanese forces were nearby or the population was unwilling to assist.
The problem of local support
One of the hardest lessons of the early operations was that pre-war knowledge did not necessarily predict wartime behaviour.
Dutch planners sometimes expected former officials, police, soldiers or other local contacts to assist returning agents.
Japanese occupation had transformed those circumstances.
Potential contacts might have been killed, imprisoned, moved or placed under surveillance. Others were unwilling to endanger themselves and their families.
Political attitudes were changing as well.
Japanese rule was often brutal, but opposition to Japan did not automatically mean support for the restoration of Dutch colonial rule.
This became particularly important on Java and in other areas where Indonesian nationalism had developed strongly.
Successful clandestine intelligence therefore depended upon a much more sophisticated understanding of local conditions than simply identifying contacts who had been considered reliable before the war.
From costly beginnings to changing methods
The heavy losses suffered by the early NEI Section parties influenced later NEFIS operations.
Training and planning improved. Greater attention was paid to communications, local conditions and extraction arrangements.
The changing military situation also helped.
In 1942, parties might be inserted hundreds or thousands of kilometres beyond Allied-controlled territory. By late 1944 and 1945, Allied forces had advanced through New Guinea and established forward bases much closer to the eastern Netherlands East Indies.
Morotai became particularly important after Allied forces landed there in September 1944.
The island, in today’s North Maluku province of Indonesia, developed into a major Allied forward base supporting operations towards the Philippines, Borneo and the Netherlands East Indies.
This brought aircraft, naval forces and intelligence organisations considerably closer to their operational areas.
ADVANEFIS at Morotai
The changing geography of the war was reflected in the creation of an advanced NEFIS presence at Morotai.
Known as ADVANEFIS — Advanced Echelon NEFIS — it allowed intelligence personnel to operate closer to Allied forward commands and to the territories into which parties were being inserted.
This shortened communications and transport links and enabled NEFIS to support the accelerating Allied advance.
The surviving Nationaal Archief collection includes a separate residual archive of ADVANEFIS at Morotai, demonstrating the importance of this forward intelligence presence.
By this stage, NEFIS was no longer attempting to conduct operations solely from distant bases in southern Australia.
Its operational network was moving north with the war.
Party APPLE and Tarakan
One of the later missions illustrates both the improved operational reach and the continuing difficulties.
Party APPLE was inserted on the Borneo coast south of Tarakan in January 1945.
The party consisted of Dutch and Indonesian personnel and was commanded by Lieutenant Oscar Drijber. Its purpose was to obtain intelligence relevant to future Allied operations in the Tarakan area.
The insertion was supported by Dutch Catalina aircraft.
Despite the improved Allied position, APPLE demonstrated that clandestine operations remained extraordinarily difficult. The party was quickly compromised and was withdrawn after only a short period.
Its members were successfully extracted, but the mission produced limited results.
The operation is examined separately in this Research Portal through the story of Dutch naval aviator Wil Hamers and the Catalina intelligence missions.
Supporting the Allied advance
By 1945 the role of NEFIS was changing.
The Allies were now entering or approaching territories that had been inaccessible since 1942.
Intelligence personnel could support conventional forces with geographical information, maps, interrogation, captured documents, interpreters and knowledge of local conditions.
NEFIS personnel were attached to or worked alongside Allied commands during operations towards the NEI.
This was a different intelligence environment from the desperate clandestine penetrations attempted three years earlier.
Rather than trying simply to establish whether Japanese forces occupied a particular area, NEFIS could increasingly contribute directly to operational planning for Allied forces approaching Dutch territory.
Operations in Borneo and Celebes
The official Australian special-operations history records NEFIS participation in several operations during the final months of the war.
A NEFIS member participated in PLATYPUS XII in Borneo in July 1945.
NEFIS also assumed responsibility for intelligence activity in the north-eastern Celebes and Manado sector, while its personnel provided interpreting and regional expertise elsewhere.
Captured documents could be passed to NEFIS for examination because of its language capabilities and specialist knowledge of the Netherlands East Indies.
These activities demonstrate how far the organisation had developed from the improvised parties of 1942.
Project SALMON
Another ambitious late-war plan was Project SALMON.
Between April and July 1945, SRD and NEFIS developed a joint proposal for a chain of small clandestine bases extending westwards from Dutch-held territory towards Java.
The intention was to establish a line of communication and intelligence posts across islands in the eastern archipelago.
Responsibility was divided between SRD and NEFIS, with NEFIS allocated five of the proposed eight bases.
A base was established on Damar, while another at Goenoengapi was partly supplied before the project was suspended.
SALMON is significant even though the complete network was never established.
It shows that by 1945 NEFIS was participating in sophisticated joint planning on a scale very different from the small, isolated intelligence parties attempted during 1942.
From the Prinses Irene Brigade to Korps Insulinde
Another strand of Dutch special operations developed not in Australia, but from Dutch forces in Britain and Ceylon.
Following the German occupation of the Netherlands in 1940, Dutch military personnel who had reached Britain were brought together in what became the Royal Netherlands Brigade. In August 1941 Queen Wilhelmina gave it the name Koninklijke Nederlandse Brigade Prinses Irene — the Royal Netherlands “Prinses Irene” Brigade.
After Japan entered the war in December 1941, the Dutch government decided to send a detachment of approximately 150 men from the brigade to reinforce the defence of the Netherlands East Indies.
The detachment left Britain in January 1942, but the Japanese advance overtook it. By the time the men reached Colombo in Ceylon in March, the Netherlands East Indies had fallen.
The original purpose of the deployment had therefore disappeared.
Dutch authorities subsequently considered using some of the stranded soldiers for a very different form of warfare: clandestine operations against the Japanese in the occupied Netherlands East Indies.
Volunteers were selected for special training in India and Ceylon. They were instructed in weapons, explosives, amphibious operations, fieldcraft and techniques described at the time as “silent killing”. Because many of the men had little or no previous experience of the Netherlands East Indies, training in languages and knowledge of local peoples and cultures was also important.
On 1 August 1942, this special-operations formation was formally established as Korps Insulinde, initially under KNIL Major Frits Mollinger. Its principal operational area became Sumatra. Dutch Ministry of Defence historical research records that the unit eventually carried out eleven operations there involving infiltration and intelligence gathering.
The connection with the Prinses Irene Brigade is therefore direct: Korps Insulinde grew out of the detachment originally sent from the brigade to fight conventionally in the Netherlands East Indies.
Two developing Dutch special-operations networks
Korps Insulinde and the Dutch intelligence operations developing from Australia were related, but they should not be treated as though they were originally the same organisation.
In Australia, Dutch and Indonesian personnel were participating in the NEI Section of IASD and subsequently in the special-operations structure of NEFIS.
In Ceylon, Korps Insulinde developed from the Prinses Irene Brigade detachment and operated within the British special-operations environment. It later became associated with Force 136, the Special Operations Executive organisation operating against Japan in Southeast Asia.
The two strands increasingly intersected.
Personnel, intelligence requirements and operational responsibilities could move between Dutch and Allied organisations. Members of Korps Insulinde became connected with NEFIS special operations, while Dutch authorities attempted to coordinate clandestine activities directed towards the occupied NEI.
This helps explain why Korps Insulinde sometimes appears in accounts of NEFIS III even though its origins lay elsewhere.
A second link with the Prinses Irene Brigade
Korps Insulinde was not the only Dutch commando formation to emerge from personnel associated with the Prinses Irene Brigade.
In Britain, another group of Dutch volunteers underwent British commando training. On 22 March 1942, 48 volunteers began the training process that led to No. 2 (Dutch) Troop of No. 10 (Inter-Allied) Commando. The Dutch Ministry of Defence regards this as the beginning of the modern Dutch commandos.
Some members of No. 2 (Dutch) Troop later reinforced Korps Insulinde for operations in Asia.
There were therefore two important Dutch special-forces developments originating from the wartime Dutch forces assembled in Britain:
- No. 2 (Dutch) Troop developed within the British commando organisation and fought in the European theatre.
- Korps Insulinde developed in Ceylon for clandestine operations against Japan in the Netherlands East Indies.
Both contributed to the traditions from which the postwar Dutch Korps Commandotroepen developed.
The connection with NEFIS III
For this Research Portal, the important point is that Dutch clandestine operations against Japan cannot be explained solely through the organisational history of NEFIS in Australia.
By 1942, Dutch special-operations capabilities were developing along several routes.
The NEI Section in Australia brought together Australian, Dutch and Indonesian personnel for missions into the occupied archipelago.
Korps Insulinde in Ceylon developed from the Prinses Irene Brigade detachment for operations particularly directed towards Sumatra.
NEFIS III subsequently became the principal Dutch special-operations intelligence structure operating from Australia.
As the war progressed, personnel and operational connections increasingly crossed these organisational boundaries. What emerged was not a single neatly structured Dutch commando organisation, but a network of Dutch and Indonesian intelligence and special-operations personnel working through Dutch, Australian and British structures.
That broader history is essential for understanding NEFIS III.
Intelligence beyond Japanese military movements
The intelligence sought by NEFIS was not confined to Japanese troop positions, airfields and shipping.
As the Allies approached the Netherlands East Indies in 1945, information about political and administrative conditions inside occupied territory became increasingly important. Dutch authorities needed to understand what had happened during three years of Japanese occupation and what conditions they would encounter when they returned.
A surviving Australian War Memorial file provides a revealing example.
In July 1945 the Allied Intelligence Bureau issued Report No. 496, based on a Netherlands Forces Intelligence Service project, containing information extending from Java to Flores. Significantly, the report included information about the organisation of collaboration established under Japanese occupation.
This illustrates the widening role of NEFIS during the final phase of the war. Intelligence was no longer concerned solely with locating Japanese forces. It increasingly encompassed political organisations, local administrations, collaboration, population attitudes and the conditions Dutch authorities expected to encounter following liberation.
That intelligence would inevitably overlap with preparations for restoring civil administration through NICA and, increasingly, with the emerging political struggle over Indonesia’s future.
Intelligence becomes civil affairs
As Allied forces recovered territory, the distinction between intelligence and administration began to change again.
The Netherlands Indies Civil Administration (NICA) accompanied Allied forces into areas liberated from Japan and was intended to restore Dutch civil government.
Intelligence about populations, political conditions, officials, infrastructure and local organisations therefore became directly relevant to civil administration.
The Australian official special-operations history shows that NICA personnel also became involved in guerrilla and intelligence activities in the Moluccas and elsewhere, sometimes with assistance from SRD.
The transition was therefore not simply from NEFIS intelligence to NICA administration. Intelligence, special operations and civil affairs overlapped as the Dutch attempted to re-establish authority.
This development is examined separately in the NICA article in this Research Portal.
A record of courage and loss
The history of NEFIS III is sometimes told through codenames: TIGER, WALNUT, LION, APPLE, SALMON, PLATYPUS and many others.
Behind those names were people.
Dutch officers, Indonesian soldiers and agents, wireless operators, aircrew and sailors entered operations in which capture could mean interrogation, torture and execution.
Many did not return.
Their missions did not always succeed and some were based on assumptions that proved disastrously wrong. Those failures form an essential part of the historical record because they influenced the development of later operations.
But the story is also one of adaptation.
Between 1942 and 1945, Dutch intelligence operations developed from participation in an improvised Allied organisation in Australia into a substantial intelligence service capable of training its own personnel, maintaining forward bases and working alongside Allied forces returning to the Netherlands East Indies.
NEFIS III was the clandestine operational edge of that development.
Its history cannot be separated from Australian support, nor from the Indonesian personnel whose knowledge and participation made many of its operations possible.
A note on terminology
The designation NEFIS III is widely used for the special-operations component of NEFIS. However, wartime organisational arrangements changed over time, and individual operations were transferred between Australian and Dutch organisations.
For that reason, this Research Portal distinguishes between operations undertaken by the earlier NEI Section of IASD and those properly associated with the later NEFIS special-operations organisation.
This distinction is particularly important when discussing early operations such as FLOUNDER, TIGER and WALNUT.
Sources and further reading
- Nationaal Archief, The Hague, Access 2.10.62 — archive of the Marine and Leger Inlichtingendienst, Netherlands Forces Intelligence Service and Centrale Militaire Inlichtingendienst. Its wartime inventory includes separate records for NEFIS special operations and Allied special operations.
- National Archives of Australia, A3269, H7, Item 235285 — NEI Section IASD. Essential for distinguishing the early NEI Section operations from the subsequent NEFIS organisation.
- National Archives of Australia, Item 235327 — Official History of Operations and Administration of Special Operations – Australia (SOA), Vol. 2 Operations.
- Peter Dunn OAM, Dutch Involvement in Special Operations — research based principally on the Australian official special-operations history, tracing the transition from the NEI Section through NEFIS to NICA.
- J.J. Nortier, Acties in de Archipel: De intelligence-operaties van NEFIS-III in de Pacific-oorlog (1985).
- Jonathan (Jack) Ford, Allies in a Bind: Australia and the Netherlands East Indies in the Second World War.
- L. de Jong, Het Koninkrijk der Nederlanden in de Tweede Wereldoorlog, Deel 11c: Nederlands-Indië III.
- Australian War Memorial, Allies in Adversity: Australia and the Dutch in the Pacific War.
- Australian War Memorial, AWM54 424/2/1, Allied Intelligence Bureau Report No. 496 — Netherlands Forces Intelligence Service Project: Information, Java to Flores, including information re-organisation of collaboration established by the Japanese, July 1945. Official Department of Defence record demonstrating the type of political and administrative intelligence being produced by NEFIS and circulated through the Allied intelligence system during the final months of the war.
