Lithuania discovers migrant tunnels, blames Belarus in hybrid warfare campaign

Lithuania's border guards have begun finding tunnels beneath the ground along the Belarusian frontier—passages that migrants are using to slip into the country undetected. Since the start of 2026, authorities have discovered a dozen of these underground routes, some stretching as long as 25 meters on the Lithuanian side of the border. The discovery has set off alarm bells among security analysts and government officials, who see the tunnels not as the work of desperate migrants alone, but as part of a coordinated campaign by Belarus to destabilize a NATO member state.

The Lithuanian border runs roughly 700 kilometers against Belarus, with about 550 kilometers of that distance now fenced. To detect the tunnels, the State Border Guard Service relies on seismic monitoring systems that pick up the vibrations of sustained digging. When the ground sensors register activity, guards position themselves near the tunnel exit and wait. When migrants emerge, they are arrested. So far, this method has netted approximately 40 people. The prosecutor's office has opened investigations into roughly 20 individuals suspected of illegally excavating tunnels and organizing smuggling operations.

General Rustamas Liubajevas, who commands Lithuania's border guard service, expressed puzzlement at the sheer effort migrants would invest in such a risky crossing. The tunnels require substantial materials—timber to shore up the walls, tools, coordination—and the success rate is abysmal. Most groups are caught within moments of breaking through. Yet the tunnels keep appearing, which led Liubajevas to a troubling conclusion: the migrants cannot be working alone. He believes Belarus is providing logistical support, keeping the border in a state of perpetual tension. The Belarusian government has repeatedly denied any role in facilitating migration flows.

Margarita Seselgyte, a political scientist at Vilnius University's Institute of International Relations and Political Science, agrees with Liubajevas's assessment. Belarus sits outside the natural migration corridors from Afghanistan, Iran, or Sri Lanka—the countries from which most migrants originate. For tunneling to occur at the border, Minsk would have to at least be turning a blind eye to the digging. More likely, she argues, the state is actively enabling it. She frames the tunnels as a form of hybrid attack designed to sow anxiety and instability within Lithuanian society. As Lithuania has reinforced its border fence and closed vulnerabilities, Belarus has simply found a way around it—literally beneath it.

For Seselgyte and other analysts, the tunnels are part of a larger pattern stretching back years. In 2021, tens of thousands of migrants surged across the borders of Lithuania, Poland, and Latvia from Belarus in what the European Union characterized as state-sponsored instrumentalization of human beings. That crisis has since subsided, thanks to coordinated border security measures across the region. Lithuania recorded 1,652 irregular entry attempts in 2025. But the tunnels represent a new phase of the same strategy: using migration as a weapon to exhaust resources, provoke political division, and weaken resolve on NATO's eastern flank.

The broader context matters. Russia launched its full-scale invasion of Ukraine in February 2022 partly from Belarusian territory. Lithuania has been vocal in its support for Ukraine and its calls for European unity against Russian aggression. By creating chaos at home—by forcing border guards to dig up tunnels, by generating public anxiety, by straining resources—Belarus and its Russian ally hope to silence that voice and fracture Western cohesion. Robert Gonzci, an analyst at the Migration Research Institute in Budapest, notes that using migration as a strategic tool is far from new. Governments have weaponized population movements for centuries, even the Assyrian empire in the seventh century BC. It is a low-cost, low-risk method of applying pressure. Democratic states face an inherent trap: they must secure their borders to protect sovereignty, yet they are bound by legal and humanitarian obligations that authoritarian regimes can ignore.

Lithuania and its neighbors are fighting back with technology and cooperation. The country is testing Polish scanning equipment designed to detect underground voids. If the systems prove effective, Lithuania plans to deploy them widely. The Nordic and Baltic states, along with Poland, are coordinating their responses to shared threats. The EU's Frontex border mission is providing additional resources. These measures have helped bring irregular migration to near-minimal levels in recent years. But experts warn that the tunnels will likely continue unless Belarus itself addresses the root causes—and that seems unlikely. As long as Minsk sees destabilization as strategically useful, the digging will go on.