Indonesian Pro-Islamic State Groups’ Attempts to Centralise Command Structures

Indonesia’s terrorist groups are currently at their lowest ebb. On the one hand, Indonesia’s most active terrorist network in the past decade – pro-Islamic State (IS) organisations like Jemaah Ansharut Daulah (JAD) – has not conducted any attacks in the last two years and has continued to plan fewer operations each year. While JAD still follows IS developments abroad, it now lacks the capacity for international travel, unlike during IS’s 2014 surge. On the other hand, the country’s largest terrorist organisation, former al-Qaeda affiliate Jemaah Islamiyah (JI), officially disbanded in mid-2024 and has pledged to abide by Indonesian laws. While some senior members may dissent, those who supported the disbandment have actively demonstrated their commitment – surrendering the identities of JI’s military wing members and handing over their remaining firearms and explosives.  

Despite this weakening state, some terrorist milieus remain active. Indonesian pro-IS groups, for instance, remain resilient online and are experiencing “a renaissance on Facebook” and other platforms. More concerningly, investigations into terrorism suspects arrested within the past two years reveal that some pro-IS networks have, for a time, succeeded in creating a centralised, cross-regional command structure. A key example of this is Abu Oemar’s pro-IS network, which, between 2021 and 2023, successfully recruited over 40 members and developed interconnected cells across major Java provinces. While this does not suggest an imminent resurgence of Indonesian pro-IS groups, it does mark a significant development in organisational capability for a terrorist network long known for its decentralised and disorganised structure. 

This article examines Indonesian pro-IS groups’ attempts to create a centralised, cross-regional network. Using publicly available court documents, it analyses three key case studies: the formation of Abu Oemar’s network (2021–2023), the initiative by former JAD Medan members to unite North Sumatra’s pro-IS cells (2016–2017), and the efforts of a pro-IS cell in Lampung to merge with another radical organisation, the Khilafatul Muslimin (2019). The article concludes with the finding that, while most pro-IS centralisation attempts fail, those that succeed typically hinge on three crucial factors: the leadership of an authoritative figure with cross-group legitimacy, the presence of pre-existing social ties between group members that enable initial coordination attempts, and the implementation of a flexible strategic framework capable of accommodating members’ diverging operational priorities. 

Case Studies 

Abu Oemar’s Halaqoh Network 

The most recent centralisation attempts by pro-IS groups were the creation of Abu Oemar’s halaqoh (study group) network in 2021. A pro-IS recidivist, Abu Oemar began his longstanding terrorist career in 1990 when he joined Darul Islam’s (DI) Greater Jakarta branch. He split from DI in 2000 to form the Abu Bakar Battalion (ABB) but rejoined the group in 2005. By 2009, he had become the head of DI’s Greater Jakarta branch, where he organised training camps in West Sulawesi and planned attacks on Jakarta’s Shi’a communities and police. In 2011, he was arrested for smuggling arms from Mindanao and was sentenced to eight years. He then pledged his allegiance to IS in prison around 2014 before being released in 2019. 

In 2021, Abu Oemar started leading multiple halaqoh across Jakarta and West Java. Court records revealed that he established these networks as part of a broader strategy to standardise different pro-IS groups’ ideological outlook and establish logistical channels for setting up training camps and firearms smuggling routes between the Philippines and Indonesia. Court documents from members of later-established halaqoh indicated that social ties were key to the creation of new cells. These ties not only helped Abu Oemar identify pro-IS groups suitable for merger – as in the case of Halaqoh Cengkareng, which was formed from a group led by his former DI and ABB associates – but also played a key role in growing existing halaqoh – as seen in Halaqoh Muara Angke, which recruited members through its coordinator’s family and close friends. 

Ultimately, Abu Oemar’s attempt to establish a cross-regional pro-IS network succeeded. By his re-arrest in 2023, his network had over 42 members who were affiliated with different groups, including Anshor Daulah, DI, Hizbut Tahrir Indonesia, Khilafatul Muslimin, and Fikroh Abu Hamzah. The network itself was relatively well-structured: members were clustered into 13 halaqoh spread across West Java, DKI Jakarta, and Banten, with each halqoh having a designated coordinator responsible for recruitment, inter-halaqoh communication, and scheduling monthly meetings. While Abu Oemar never established training camps or firearm smuggling routes, he did inspire his followers to plot attacks. Simply by urging them to “do what they can” to “disrupt the 2024 general elections,” members from his Halaqoh Taruma Jaya began conducting i’dad (training) and preparing attacks on voting booths and police – before being promptly arrested. 

Former JAD Medan Members’ Unification Attempts 

A second case of centralisation attempt by Indonesian pro-IS groups involved the efforts of former JAD Medan members in 2016 to unite pro-IS cells across Sumatra. JAD Medan is an unofficial branch of JAD led by a man named Rulianto –– a former DI member who turned to support IS in 2014 due to engaging with IS content online. Along with his friend Rony, Rulianto formed JAD Medan in 2015. By April 2016, however, internal disagreements emerged when Rulianto rejected Rony’s proposal to merge the group into the local branch of the National Anti-Shi’a Alliance. Consequently, Rulianto and 10 other members left to form an independent group named Anshor Daulah (AD) Medan. 

Following the split, both groups quickly sought to recover from their loss of members by pursuing mergers with other pro-IS cells in the region. By July 2016, AD Medan had held numerous meetings with pro-IS cells of the neighbouring Tanjung Morawa district and Tanjung Balai city to discuss “the future of JAD groups in North Sumatra” and create a new, unified structure under Rulianto. Similarly, the remaining JAD Medan members, now led by Rony, also pursued centralisation efforts as they believed that their group lacked the manpower to defend against possible Shi’a attacks in Indonesia. In March 2017, JAD Medan began visiting various pro-IS groups in Riau Province, South Sumatra, and Lampung Province to propose the creation of a unified structure. 

Ultimately, Rulianto’s and Rony’s centralisation attempts failed. Although Rulianto initially managed to organise several joint training sessions with the pro-IS cells from Medan, Tanjung Morawa, and Tanjung Balai, his bid for unification quickly collapsed due to his unwillingness to accommodate members’ differing strategic visions. By October 2017, tensions surfaced when he forbade Tanjung Balai members from launching attacks, prompting them to break away and appoint a new leader. Rony’s attempts, meanwhile, never progressed beyond discussions due to his failure to persuade the region’s major JAD networks to join. This was particularly evident in his unsuccessful effort to recruit JAD Lampung, whose members flatly rejected the proposal, arguing that Rony lacked the authority to initiate such structural changes because he was not the recognised head of JAD North Sumatra. 

Lampung Pro-IS Cells’ Merger Attempts 

The third case study involves the attempts by an unnamed pro-IS cell in Lampung to merge with the Khilafatul Muslimin (KM) – a pro-Caliphate, non-violent Islamic organisation headquartered in Lampung. Formed in 2019, the Lampung cell was led by Saheh. Saheh had previously been part of KM but left in 2018, frustrated by the group’s inaction toward establishing a Caliphate. He then recruited three former KM colleagues from Lampung, and in April 2019, added a fourth member, Adnan. A fugitive affiliated with KM and a pro-IS cell in West Java, Adnan was introduced to the Lampung cell by his friend and fellow member, Faruq. Recognising Adnan’s bomb-making experience and links to Java IS networks, Saheh agreed to shelter him. 

Following the cell’s formation, Saheh showed great interest in unifying the region’s pro-IS and KM networks. Court documents noted that Saheh viewed this unification as a crucial solution to both the pro-IS network’s “lack of structure and command” and KM’s “lack of action and drive.” However, not all members agreed. Adnan, for example, stated that he “did not care if KM and pro-IS cells joined” because he “wants to hijrah [depart] to Southern Philippines or, if that fails, conduct a suicide bombing [in Indonesia].” Despite disagreements, Saheh maintained that unification was essential. Believing that KM would only consider the proposal if it was delivered by a respected pro-IS ustadz with strong religious authority, Saheh instructed Adnan to return to and use his networks in West Java around mid-2019 to find one. 

Ultimately, the Lampung cell’s unification never materialised. Over time, Saheh began to lose interest in the unification agenda and increasingly prioritised attacks. When the topic of unification was brought up during a meeting in August 2019, Saheh abruptly redirected the topic to focus on the issue of explosives and their procurement. Moreover, when Adnan returned to Lampung in October 2019, he did not bring with him any ustadz he thought suitable for the unification project, nor did he mention anything about his attempts to find one. Instead, he brought a package containing bomb-making chemicals and urged the Lampung cell to “conduct amaliyah (attacks) and free other imprisoned terrorists.” Authorities eventually arrested the group later that month, halting their activities. 

Factors of Success 

The Key Role of Leaders 

As the case studies show, Indonesian pro-IS groups’ efforts at centralising command structures often fail. However, when such efforts succeed, three factors are often present. The first is the presence of a leader who holds cross-group legitimacy and is cognisant of the group’s operational deficiencies. Notably, a leader’s authority plays a critical role in determining whether other groups perceive the centralisation efforts as credible. This was evident in the Lampung cell’s attempted unification with KM, where members acknowledged that such a merger would only be seriously considered if it was proposed by a “respected pro-IS ustadz.” When centralisation attempts are proposed by group leaders who have no recognised authority, such as in the case of Rony’s attempt to convince JAD Lampung to merge with JAD Medan, they are often rejected. 

Indeed, a key reason why Abu Oemar’s centralisation attempts succeeded was because the halaqoh cells he reached out to all revered him and his long jihadist experience. As noted by Abdul Halim, Halaqoh Muara Angke’s coordinator, many recidivists agreed to join Abu Oemar’s halaqoh because he was “the most senior and experienced figure” they knew. Similarly, Nisran, the Halaqoh Cengkareng’s coordinator, agreed to merge his group with Abu Oemar’s because he had developed great respect for him in 2009 when the two of them worked together in DI’s Greater Jakarta branch. Nisran’s testimonies even noted that he only embraced IS ideology in 2014 after learning that Abu Oemar had done so. 

Beyond legitimising centralisation proposals, leaders also play a decisive role in initiating the very idea of unification. For terrorist groups to consider any form of cooperation, they must first recognise their own resource constraints. In all of the case studies above, such recognition was largely prompted by group leaders. For example, Abu Oemar’s network only formed due to his desire to address the “lack of standardised ideology between various [pro-IS] groups.”  Similarly, the Lampung cell began its unification efforts with KM’s network on the basis of Saheh’s assessment that pro-IS groups are in a state of disarray. Without leaders who were cognisant of their group’s deficiencies, the very idea of centralising commands between Indonesian pro-IS groups would likely not have emerged. 

Pre-Existing Social Ties 

A second factor that accompanied successful centralisation efforts is the presence of pre-existing social ties between group members. Like other forms of cooperation between terrorist groups, a factor that significantly inhibits successful centralisation initiatives is the groups’ lack of accessible communication points. Due to terrorist groups’ inherently clandestine nature and the constant risk of state surveillance, groups rarely advertise how others can contact them. Pre-existing personal relationships between different groups’ members help address this challenge by serving as trusted, pre-established channels through which initial coordination can occur. Indeed, in every case study, early communication efforts between cells were done through leaders’ and members’ personal connections.  

One key example of this was JAD Medan’s unification attempt. Notably, one of the first pro-IS cells JAD Medan visited in their March 2017 unification tour was in Dumai, Riau Province. Here, Rony met and successfully convinced his friend, Darwis, to endorse JAD Medan’s centralisation initiatives. Through Darwis’ network and introduction, Rony was able to then contact other pro-IS groups in the region, including Aznop in Pekanbaru, Sholihin in Muara Enim, and Danir in Lampung. The key role of social ties in facilitating initial centralisation outreach was also evident in Abu Oemar’s case. The merger of a local pro-IS study group in Tajur Halang into his Halaqoh Cengkareng, for example, was only possible because he knew one of the study group’s members, Agus – who had previously served under his ABB unit – and thus knew how to contact him. 

Beyond aiding initial coordination, pre-existing relationships are also crucial in accelerating groups’ growth. This was most evident in the case of Abu Oemar’s network. For instance, after Abdul Halim became coordinator of Halaqoh Muara Angke, he primarily drew recruits from his immediate circles – bringing in his children, enlisting recidivist colleagues, and assigning his cousin to manage the group’s Telegram channel. A similar pattern occurred with Jumadi, the coordinator of Halaqoh Kemang. After joining the network in 2022, he leveraged his ties as a former staff member of the pro-IS madrassah Pondok Pesantren Ibnu Mas’ud to recruit former colleagues. That said, while pre-existing social ties are important in initiating centralisation efforts, they do not guarantee success, as such ties were present in all case studies regardless of their outcome. 

Flexible Strategic Framework 

A third factor that accompanied successful centralisation efforts is the leader’s implementation of a flexible strategic framework. In all three cases, group leaders pursued centralisation primarily as a way to rebuild their network. Consequently, attacks were generally deprioritised, with some leaders even viewing them as counterproductive since they often led to arrests, which could jeopardise the group’s long-term goals. However, due to differences in how members understand the group’s goals, they often do not share leaders’ visions – favouring immediate action over patient rebuilding. Evidently, all three centralisation cases had members who strongly pushed for their groups to prioritise attacks. In the Lampung cell’s case, for example, Adnan was vocal in his rejection of Saheh’s vision to merge the group with KM because he believes that it would not help him conduct attacks in the Philippines or Indonesia. 

When Indonesian pro-IS cells succeed in forming cross-regional collaborations, networks only endure when leaders are willing to adapt their strategic goals and accommodate members’ desire to conduct attacks. Indeed, Abu Oemar’s network – the only successful case – was led by a figure notably open to members’ plans for attacks. While Abu Oemar never directed any of his cells to conduct attacks and only envisioned the group to coordinate such operations after they had established support structures in the Philippines, Abu Oemar also never restricted members from planning attacks independently. Not only did he encourage members to do what they can to “disrupt [Indonesia’s 2024 elections],” he even ordered other members to “not mock” those who plan to carry out attacks. 

However, regardless of the path leaders choose – whether accommodating or rejecting members’ desire to launch attacks – they often find themselves facing a lose-lose situation. On the one hand, as evident in AD Medan’s case, when leaders prohibit attacks outright, members may splinter off and form new groups. On the other hand, as Abu Oemar’s case shows, accommodating members’ inclination towards violent actions may preserve cohesion but also heightens the risk of detection. Indeed, the eventual collapse of Abu Oemar’s network was largely triggered by police action against members who were plotting attacks on voting booths. While more established organisations may avoid this dilemma by enforcing internal disciplinary measures or cultivating compliance norms, newly merged groups lack the luxury of time needed for these kinds of institutionalisation. 

Conclusion 

Despite its weakened state, not all Indonesian pro-IS groups are idle. Over the past decade, several groups have demonstrated the intent and capability to address operational deficiencies by forming more centralised, cross-regional command structures. As of now, these centralisation attempts have had little impact on Indonesia’s overall national security, as most of them ultimately failed. When centralisation attempts do succeed, it was made possible by three crucial factors: the presence of an authoritative leader who not only recognises their group’s limitations but also holds enough credibility across different groups to legitimise the centralisation effort; pre-existing social ties among members that can serve as trusted channels for initial coordination; and a flexible strategic framework that allows the group to accommodate members’ diverging operational priorities. 

This article offers two key lessons. First, there is a pressing need for Indonesia to better monitor the reintegration of recently released, senior pro-IS figures. As shown above, successful pro-IS centralisation often relies on leaders whose social ties and credibility reach across multiple groups – traits typically found among senior recidivists with long-standing jihadist experience. While Indonesia’s terrorist recidivism rate is relatively low, the exponential increase in arrests post-2018, combined with the slow implementation of countering violent extremism reforms, has left the system increasingly overstretched and under-resourced. Consequently, while high-profile terrorists like Umar Patek receive significant reintegration support, lesser-known individuals such as Abu Oemar are still overlooked – allowing them to reconnect with old networks. Without addressing these problems, the release of senior terrorist inmates will continue to pose a risk to the rebuilding of pro-IS groups. 

Secondly, Indonesia must sustain the monitoring of pro-IS networks’ rebuilding attempts. Although these groups have historically been described as less professional, these case studies demonstrate that some pro-IS groups are capable of prioritising long-term structural growth over immediate violence. These efforts will be particularly challenging today, as Indonesia’s counterterrorism apparatus must simultaneously manage the reintegration of 8,000 former JI members following the group’s 2024 dissolution, while also contending with the National Counterterrorism Agency’s 69 percent budget reduction in 2025. However, just as Indonesia’s complacent monitoring of JI in the 2010s gave them space to rebuild, neglecting pro-IS groups’ early centralisation attempts risks providing them the same opportunity to re-establish a presence in the country.

This article represents the views of the author(s) solely. ICCT is an independent foundation, and takes no institutional positions on matters of policy unless clearly stated otherwise.

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