Every day, nondescript buses carrying passengers from occupied Ukraine cross through Poland and the Baltics into the European Union.
Among those entering the bloc are people who’ve spent years under Russian occupation, exposed to propaganda, coercion and russification campaigns.
Experts warn that these residents of occupied territories — traveling with Ukrainian passports and facing less scrutiny at the border — could pose a security threat to the EU.
The route is accessible enough, according to Petro Andriushchenko, head of the Center for the Study of the Occupation that “no one knows how many agents of influence have entered the European Union.”
As Russia's full-scale invasion of Ukraine continues into its fifth year, researchers say teh EU needs to focus more on the political and social transformation unfolding inside occupied Ukraine.
Moscow has sought to systematically convert residents into Russian loyalists. The result is “an indoctrination within people that the West is an enemy,” said Katsiaryna Lozka, a research fellow at the Egmont Institute studying occupied Ukraine.
For Europe, occupied Ukraine has increasingly become a complex security challenge — one that blends disinformation, militarization and human rights abuses into a volatile test of the EU’s geopolitical heft, and of occupied Ukraine’s chances for reintegration if liberation comes.
Buses from occupied Ukraine enter Europe
Advertisements for trips into the EU are easy to find. Small businesses post daily on Mariupol-based Telegram channels about comfortable passenger buses to the EU. “From the Luhansk, Donetsk, Zaporizhzhia and Kherson regions through Belarus and the Baltic states,” one advertisement reads.
The lack of scrutiny is a major security loophole that the EU is yet to close, according to Andriushchenko. “No person can operate such a business without FSB oversight,” he said, referring to the Russian security service. “Yet they enter Poland daily.”
Bus companies instruct passengers to leave occupied Ukraine using Russian-issued documents, enter Belarus carrying both Russian and Ukrainian passports, and cross into the EU using only their Ukrainian passport — a tactic designed to minimize scrutiny at the border. Russian passport holders need visas to enter the Schengen zone, while Ukrainians can travel visa-free.
As Russia intensifies its hybrid warfare tactics across the EU — relying on sabotage and disinformation — preventing pro-Russian operatives from entering the EU is becoming more important. Estonia and Latvia officials said they are aware of the threat and taking steps to mitigate it. Poland and Lithuania didn’t respond to requests for comment.
At the Russian-Estonian border, Ukrainians without a Russian exit stamp in their Ukrainian passport are checked for a Russian passport, according to Peter Maran, the head of Estonia's southeast border crossing.
However, Estonian border guards have found Russian passports hidden in shoes, underwear and suitcases, according to Maran. “Ukrainian citizens are considered high‑risk travelers and undergo thorough checks at every border crossing,” he said. “If Ukrainian citizens hide documents or give false statements to officials, they are denied entry into the country for security reasons.”
In Latvia, the license for the only commercial bus route from Belarus will expire on June 26 and not be renewed, according to the Latvian Ministry of Interior, which added that there are no commercial buses entering directly from occupied Ukraine.
However, the primary bus route from Belarus into Poland is still operational, according to Andriushchenko, leaving Europe exposed.
Moscow’s ‘russification’ campaign
Katerina Shevchenko, a small business owner in her thirties, lost both her job and home after Russia took control of Mariupol in 2022. And just like millions of other Ukrainians, Shevchenko, whose name has been changed for the safety of family members still living in occupied Ukraine, also experienced russification firsthand.
Russification, the imposition of Russian identity, norms and language on non-Russian populations, has been underway for over a decade in Crimea and parts of Ukraine’s Donetsk and Luhansk regions seized by Moscow in 2014.
Since 2022, the campaign has expanded across large swaths of the country’s east, according to Karolina Hird, an analyst at Institute for the Study of War monitoring the Russian campaign in Ukraine.
The process typically begins with “passportization,” forcing residents to accept Russian passports to access jobs, housing, social security and basic government services, according to Vincent Artman, a geographer studying occupied Ukraine. “It’s a way of erasing Ukrainians through legal means,” he said.
Transforming the media comes next. Shrevchenko said access to Western and Ukrainian news largely disappeared after the occupation, replaced by anti-Western propaganda on radio and television. Russian authorities have also mandated the installation of satellite dishes that only receive Russian channels, Hird said.
In school, Shrevchenko’s two children were forced to study history from Russian textbooks that portrayed Europe is an enemy, NATO as an aggressor and Russia invasion as a quest to liberate Ukrainians from Nazism.
In September 2022, Russian Ministry of education introduced compulsory patriotic education courses, named “Important Conversations.” Held every Monday after a flag raising ceremony, the lessons are meant to instill “Russian values.” In Mariupol, where Shevchenko’s children continued to attend middle school, Russian soldiers often visited classrooms.
The textbooks themselves have also changed. New editions of Russian and world history volumes, overseen by Vladimir Medinsky, widely known as Putin's historian, were rolled out in 2025. Students learn that Russia's invasion is meant to protect the Russian-speaking population in the Donbas region from “genocide,” and frame EU and NATO support for Ukraine not as backing for a sovereign nation under attack, but as an effort to maintain a U.S.-dominated world order.
From Ukrainian children to Russian soldiers
Russification has run parallel with militarization, as youth camps led by the Russian military teach children from occupied Ukraine to shoot, march and fly drones. Artman said the aim is to turn young boys “into patriotic Russian citizens who will defend the motherland.”
Women, meanwhile, are instructed to have lots of children. Artman described it as an attempt to reverse the demographic slide in occupied Ukraine and Russia more broadly, where the government needs more men for the armed forces. “There’s a fear you’ll end up with a lost generation of kids,” he said.
But some groups are fighting back against both combat russification and militarization, while providing escape routes for those still trapped in occupied Ukraine.
Valeriia Krupoderia was 11 and living in Luhansk when the Russian-backed separatist movement took over control of the city in 2014. Now she’s a project manager for Eastern Variant, a news organization that covers occupied Ukraine and provides information to Ukrainians seeking evacuation.
She’s also seen firsthand how pro-Russian propaganda can work. Before she left, her grandfather had started to believe that Sweden suffered basic food and medicine scarcity, and that European supermarkets were empty.
“People’s understanding of reality becomes distorted,” she said. “Children and adults who grow up in the Ukrainian environment twenty years ago, these people forget about this life [in free Ukraine]. Russian propaganda works like a machine.”
The EU’s role in occupied Ukraine
The EU has been a central pillar in Ukraine’s war effort, but the bloc has been less engaged with the realities in occupied Ukraine. That’s partly the result of near-total information blackout and the inability to access the territories, but also a political unwillingness to take steps that could be seen as legitimizing or normalizing Russia’s occupation, said MEP Thijs Reuten (S&D, NL), a member of the Committee on Foreign Affairs.
“Our only task is to support Ukraine to fend off Russian aggression and to make sure that that the occupied territories become part of sovereign Ukraine again,” Reuten said.
However, the EU has been more active in tackling the forced deportation of children from occupied Ukraine into Russia. It recently sanctioned 16 individuals responsible for forced assimilation, militarization and transfer of minors. In conjunction with the EU, Ukraine has also used the Schengen Information System border control database to flag possible security threats.
However, border policing is complicated by the prospect of family separation. Reuten said that while security is important, it doesn’t mean “automatically assuming that everyone that lives under the temporary occupation of Russia is also a threat.”
The central danger of russification, Artman said, is that Russia is setting up “a self-perpetuating ideological system,” within occupied Ukraine — one devised to outlast the war itself. Without a greater understanding of how that system works, the EU is exposed to security threats while also being less able to assist Ukraine in reversing years of indoctrination if occupied territories are eventually liberated.
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