India–Bangladesh Border: Islamist Radicalisation, Regime Uncertainty, and Emerging Security Threats

By Dr. Kanchan Lakshman is a national security analyst based in Delhi, India. His areas of specialisation include terrorism, radicalisation, and transnational organised crime

Introduction
India and Bangladesh share a common land border of 4096 kms (Land: 3166.624 Kms; Riverine: 930.076 Kms) in addition to the maritime border in the Bay of Bengal. The India-Bangladesh border, among the longest and most complex international borders in the world, traverses through diverse geological features, comprising hilly terrain, flat land, riverine belt, low-lying land and forested areas. It has historically presented serious difficulties for border management due to its dense population and strong cross-border sociocultural ties. However, sustained bilateral cooperation between New Delhi and Dhaka has contributed to border stabilization over the ten years preceding 2024.

This delicate balance is currently under increasing pressure. There is political unrest, growing ideological polarisation, and a concerning resurgence of Islamist radicalization in Bangladesh. Concerns regarding the future course of Bangladesh’s internal security have increased as the nation gets closer to national elections, which are set for February 12, 2026, and the possibility of political change or instability after the elections. For India, these developments have immediate and direct effects for border security.

This article examines how the India-Bangladesh border could become a new security hotspot due to political upheaval, Islamist radicalization, and the resurgence of transnational terror networks. It contends that traditional border management strategies may find it difficult to contain the multifaceted threat posed by the convergence of ideological extremism, criminal economies, and regime uncertainty.

Strategic Significance of India–Bangladesh Border
The India–Bangladesh border traverses five Indian states – West Bengal, Assam, Meghalaya, Tripura and Mizoram – regions that are socio-politically sensitive and, in few parts, historically affected by insurgency. The border frequently passes just a few meters from residential areas as it passes through towns, farms, rivers, and forests. Even during stable political environments, complete physical control is challenging due to this geography and thus presents unique challenges that complicate security management. Spanning five Indian states, the frontier navigates diverse terrain, including densely populated riverine areas, marshy lowlands, and remote forested sections. Approximately 21 percent of the border remains unfenced, with river boundaries and shifting char lands (temporary islands that form in riverbeds due to deposition of silt & sand) creating vulnerable points for cross-border movement.

Apart from geography, the border holds immense strategic significance for India. It is the eastern gateway to India’s Northeast; a region connected to the mainland by the Siliguri Corridor – the narrow stretch of land often referred to as the “Chicken’s Neck” which connects mainland India to its northeastern states. This corridor is a critical artery for military logistics, civilian movement, and strategic connectivity. Any destabilisation along this border has the potential to affect not only border districts but also the entire Northeast.

Because people on both sides of the international border frequently share ethnic and cultural ties and there are push factors of immigration, the demographic shift in the border regions – particularly in West Bengal’s Nadia and North 24 Parganas districts – has made border management even more challenging.

The border region is also very important to Bangladesh. It is a transit route, a sensitive area, and an economic lifeline. The border regions are the first to signal and enable a security breakdown when the political system is compromised or ideological extremism gains ground.

The true nature of the border is demonstrated by recent statistics. In 2025, Indian security forces detected 1,104 infiltration attempts along the Bangladeshi border, up from 977 in 2024, the highest number in nearly ten years. This trend makes the Bangladesh border a challenging area for India. The timing coincides with the political turbulence that followed the overthrow of Sheikh Hasina as Prime Minister in 2024 and the current interim government’s assessment of the agreements that it finds to be “uneven.”

Political Flux in Bangladesh
Since the Sheikh Hasina government was overthrown by a student uprising, Bangladesh’s political landscape has drastically changed. Since taking office in August 2024, the caretaker government led by Nobel Prize winner Muhammad Yunus has seen a decline in relations with India on a number of issues, particularly Hasina’s exile in India and the treatment of religious minorities in Bangladesh.

Despite the appearance of normalcy, instability remains a reality in Bangladesh in the lead-up to elections scheduled for February 12. Although the level of violence on the streets has ebbed and flowed, instances of unrest, including protests against Indian interests, have highlighted the rising level of anti-Indian sentiment, now increasingly backed by Islamist extremists. Against this precarious security environment, India has closed its visa application centers in several cities and declared Bangladesh a “non-family” posting for its diplomats and withdrawn all family members and dependents of diplomats from there – a move that reflects the breakdown of law and order. Appropriately, India’s Parliamentary Standing Committee on External Affairs, in its 9th Report, has characterized developments in Bangladesh as the “greatest strategic challenge” to India since the Liberation War of 1971, a characterization that remains valid to date as instability and radicalization show no signs of letting up.

The Awami League has been banned from political activities, and Hasina has been sentenced to death in absentia. This election is mainly between the Bangladesh Nationalist Party (BNP), led by Tarique Rahman, the son of the late former Prime Minister Khaleda Zia, and a group of Islamist parties led by Jamaat-e-Islami and the National Citizen Party, which is run by students. The BNP has put forward 288 candidates for 300 seats, while Jamaat-e-Islami, which was banned from politics in 2013 but allowed back by the interim regime, is having what is called its best election showing in many years.

There are historical precedents of how political transitions in Bangladesh have affected border stability and relations with India. In the past, when the BNP and Jamaat were in power, especially under Khaleda Zia, Bangladesh provided shelter to Indian insurgents active in the Northeast, with Zia controversially referring to these militants as “freedom fighters.” Now that these political groups are back and Bangladesh is also getting closer to Pakistan, including starting direct trade for the first time since 1971, India is worried about future security cooperation between the two countries.

Resurgence of Islamist Radicalisation
The political void after Hasina’s overthrow has allowed radical Islamist groups to revive. The caretaker government has been ‘soft’ against these Islamist groups, who had been largely suppressed under the previous regime. The contemporary security environment in Bangladesh is characterized by an expansion of Islamist radicalization and resurgence of previously suppressed jihadist networks, occurring alongside a perceived erosion of institutional guardrails. There is a discernible shift in the domestic socio-political discourse, where radical Islamist entities are increasingly beginning to prioritize a Pan-Islamic identity over the traditional Bengali nationalism – frequently leveraging geopolitical anxieties regarding Indian influence to galvanize support.

Exploiting current political volatility, several proscribed or extremist organizations – including the Jamaat-e-Islami, Hefazat-e-Islam, and Ansar al-Islam – are reportedly restructuring. Of particular concern to border security agencies is the evidence of renewed synchronization between these entities and Pakistan-based militant groups. This nexus of civil unrest, ideological hardening, and militant regrouping presents a multi-layered threat profile:

• Border Integrity: Heightened risks of infiltration and exploitation of porous border sections.
• Regional Stability: Potential for communal spillover effects into neighbouring Indian states of Northeast.
• Geopolitical Alignment: A shift in Dhaka’s external orientation, especially its warming ties with Pakistan, that may destabilize India’s Eastern security theatre.

The present resurgence is taking place through discreet methods which use socio-religious structures and welfare systems to establish community legitimacy. The specific madrassa networks function as essential elements because they provide more than basic religious education through their role as venues for transmitting anti-democratic ideas which support transnational Islamist beliefs. Encrypted digital platforms together with international networks now enable these beliefs to reach a larger audience. The process of radicalization which used to affect only low-income people now shows different demographic patterns. The recruitment process now succeeds in attracting both educated young people and professionals from cities as well as families who have migrant connections.

Extremist networks are shifting from using border regions as merely transit points to now focusing on them as their primary base of operations, as evidenced by their growing social base. By establishing their presence in society, the groups are able to pose increasingly complex threats to border management and regional security.

Re-Establishment of Pakistan-Linked Terror Networks
The ongoing radicalization in Bangladesh is compounded by the re-emergence of Pakistan-linked militant groups who seek to restore their operational activities which security cooperation between India and Bangladesh had succeeded in eliminating during the decade of Sheikh Hasina’s regime. The groups have changed their operational methods from running training camps to conducting operations through sleeper cells who work with their existing criminal and religious networks. The networks use Bangladesh’s strategic ports and its unprotected border areas to establish multiple routes through which they are trying to access India’s eastern theatre, especially with the help of active human smuggling and criminal networks.

Terror–Crime Nexus and Border Exploitation
The India-Bangladesh border is a focal point for entrenched transnational criminal activities, ranging from narcotics and counterfeit currency trafficking to human smuggling to cattle smuggling. Criminal groups also maintain an operational alliance with extremist groups. Radical groups use established illegal routes to transport weapons and personnel and illegal funds between different locations. Criminal organizations obtain protection through extremist groups which also provide them with capacities to intimidate others. This convergence transforms traditional border management challenges; border protection forces no longer face distinct criminal or ideological threats, but rather a sophisticated, hybrid ecosystem that utilizes the same porous geography for diverse hostile ends. The three types of areas which are most at risk are riverine stretches, char lands and unfenced segments. Ingress has evolved to include document fraud and demographic infiltration which can be concealed from border agencies.

The porous border, lack of economic opportunities on both sides, poverty, and people’s perception on small crimes lead to a rise in trans-border crime. Items like cattle, Phensedyl (a codeine-based cough syrup), Yaba pill (methamphetamine hydrochloride), cannabis, opium, heroin, gold, silver, cosmetics, and medicines are smuggled out of India, while gold, fake currency, and Hilsa fish are smuggled into India. Items that are in demand and can generate profit are smuggled across this border.

The Border Security Force estimates that around 20 Lakh cattle heads are smuggled each year from India to Bangladesh. The main reason is the price difference, which can go beyond Rs 25,000 per animal and rise sharply during festivals like Eid. This illegal trade is worth about Rs 8 lakh crore. It depends on established networks of middlemen (dalals) who work with officials on both sides of the border using systematic bribery.

Narcotics trafficking presents a critical challenge to the integrity of the 4,096-km border. 11,866 kilograms of narcotics were seized on the eastern front in 2024, according to the Border Security Force (BSF), accounting for 96% of all drug recoveries nationwide. Despite these significant enforcement actions, officials estimate that seizures account for only 10% of the total illicit flow.

The illicit trade is dominated by Phensedyl and Yaba which are in great demand in Bangladesh’s grey market. The recent discovery of underground storage facilities for these drugs (including an arrest in Nadia, West Bengal (India), where Police seized 62,200 bottles worth Rs 1.4 crore) illustrates how organised criminal networks are using more sophisticated means to transport and distribute these drugs. Due to the border’s riverine and porous sections, there are many opportunities to move a large number of drugs across the border. This emphasises the need to use technology and smart fence solutions to monitor and manage the entire border.

Smuggling of Fake Indian Currency Notes (FICN) is threatening India’s economic security. In 2024, BSF arrested several people with counterfeit currency notes, supported by intelligence showing organised criminal activity and production of these notes in external manufacturing hubs, facilitated by networks in Bangladesh. FICN, produced in sophisticated operations near the border, enter India through the same routes used for narcotics and are designed to destabilise the economy while funding further criminal activities.

Human trafficking and illegal migration remain a persistent concern. In 2025, Indian authorities detained over 2,550 Bangladeshi nationals, with a sharp spike to 380 arrests in October alone. This surge in illegal migration is fuelled by Bangladesh’s economic distress and political instability, alongside the influence of organized human smuggling syndicates.

Emerging Threat Vectors Along the Border
Emerging threat vectors that merit attention include the expanded use of IT by extremist and criminal groups. The use of encrypted communications, GPS to assist with navigation along rivers and use of social media for recruiting, reduces reliance on physical closeness and makes it harder to detect. The radicalization of border populations presents a dual-layered border security challenge: first, economic marginalization and extremist narratives transform local populations into permissive environments for sheltering operatives, complicating border control. Second, this ideological shift risks merging with dormant grievances in India’s sensitive Northeast, potentially creating hybrid threats that link local insurgent landscapes with broader transnational extremist agendas.

Implications for India’s Border Management
India has invested heavily in border fencing, surveillance technologies, and force deployment along the Bangladesh frontier. The Border Security Force (BSF) maintains a dense presence, supported by intelligence agencies and state police forces. Notwithstanding significant investments in fencing and surveillance, India’s border security faces evolving challenges that physical barriers alone cannot solve. Radical Islamist radicalisation, document fraud, and sleeper-cell operations require deeper intelligence penetration, community engagement, and inter-agency coordination. Riverine and marshy terrain further limits the effectiveness of static infrastructure. Moreover, prolonged political instability in Bangladesh could strain bilateral mechanisms that have previously enabled real-time intelligence sharing. As political instability in Bangladesh threatens traditional intelligence-sharing, India must recalibrate its doctrine – moving beyond mere boots on the ground to a strategy that integrates community engagement, financial intelligence, and cyber monitoring into its border management.

Regional and International Implications
The security situation along the India-Bangladesh border carries implications that also extend beyond a bilateral framework. China’s expanding footprint in Bangladesh – including a reported agreement to upgrade the Lalmonirhat airfield near India’s sensitive Siliguri Corridor – adds a geopolitical dimension to what might otherwise be treated merely as a border management challenge. China’s provision of military equipment, infrastructure financing, and diplomatic support to Bangladesh creates alternative options for Dhaka that may reduce New Delhi’s leverage on security cooperation in future.

For regional actors, it threatens to disrupt trade corridors, energy connectivity, and broader South Asian stability. For Western stakeholders, including the UK, the convergence of jihadist networks, organised crime, and migration routes raises concerns about transnational security spillovers. Bangladesh’s large diaspora, including in the UK, maritime connectivity, and role in global supply chains mean that internal radicalisation cannot be viewed as a purely domestic issue. Border insecurity in South Asia increasingly intersects with global counter-terrorism and organised crime agendas.

Prognosis
India’s eastern frontier is at a critical geopolitical inflection point. The general election in Bangladesh on February 12 will be the first of many tests for stability as well as whether Dhaka will adopt pragmatism with a nationalist stance as a BNP-led government or go the way of more confrontation with a Jamaat-led Islamic coalition. If radical militant camps revive and Dhaka’s relations with Islamabad improve, India will face a landscape where traditional border guarding is no longer sufficient. To secure its “Chicken’s Neck” (Siliguri Corridor) and stabilize its Northeast, India must transition to a whole-of-government border doctrine. Such a strategy will require nuanced fusion of unilateral vigilance – leveraging advanced surveillance and intelligence – with community engagement and economic development to protect border populations against extremist narratives. India’s response to Bangladesh must balance a strong security response with the use of strategic patience, maintaining channels of diplomatic communication throughout the entire spectrum of Bangladesh’s polity, to ensure functional friction does not amount to a long-term strategic loss for India.

N.B. Since this article was submitted the General election was held in Bangladesh. It was the first general election since the July Uprising of 2024 that ended the 15-year-long rule of Sheikh Hasina. The Bangladesh Nationalist Party (BNP), led by Tarique Rahman, won a landslide victory in the election, securing two-thirds of seats; Bangladesh Jamaat-e-Islami secured the second most seats.