As they settle into their seats, a priest dressed in flowing cream-coloured robes takes to the altar to deliver the weekly sermon, followed by a short prayer for peace and security in the region.

The once-bustling Sunday service has become a solemn and sparsely populated event since Moscow launched its assault on Kyiv in February 2022.

Like residents of dozens of eastern Lithuanian towns along the border with Russia’s closest wartime ally Belarus, residents in Barvoniskes trickled out of their hometown over recent months. They fear an imminent Russian invasion of their country as the war on Ukraine rages on.

With the small Baltic state sandwiched between Belarus to the east and the heavily militarised Russian enclave Kaliningrad to the south, Lithuania – a NATO member with a population of nearly three million – has been deeply affected by the Russia-Ukraine war.

Wary that their capital Vilnius sits only 50km (31 miles) from Belarus, Lithuanian authorities beefed up border security with the start of the war and hastened the erection of a border fence initially intended to deter irregular migration into the EU.

But despite ramping up defence funding and border security, Lithuania’s border region has turned into a ghost town with residents deserting their homes in search of work opportunities and security elsewhere.

“It is no longer safe around here,” 68-year-old Rozalija, a Lithuanian housewife living in Barvoniskes, told Al Jazeera as she walked out of the old church with a small handkerchief in her hand.

Like many of the younger generation, Rozalija’s three adult children left Barvoniskes last year.

“We barely see anyone any more – everyone’s left,” she said.

Migration crisis

Formerly part of the Soviet Union, Lithuania’s animosity with Russia extends decades into the past, but its recent security crisis began months before the war on Ukraine.

After the European Union (EU) imposed sanctions on Belarus and its longtime president, Alexander Lukashenko, in April 2021 over what it perceived as fraudulent elections, the EU member state saw a dramatic rise in the number of undocumented migrants crossing over the Belarusian border to enter the EU through Lithuania.

Lithuania responded by accusing Belarus of orchestrating a mass influx of irregular migrants from Africa and the Middle East, which it estimated in August 2021 to be more than 4,000 over the past year.

As an initial response to the situation, Vilnius ordered in July 2021 the building of a 520km (323-mile) fence along its border with Belarus.

With the start of the war on Ukraine, Vilnius approved an exceptional budget of 152 million euros ($169m) to speed up building of the border fence – which it completed in August 2022 – and gave border guards the right to turn away migrants.

While Belarus has denied the accusations, Vilnius demands 120 million euros ($133m) in compensation from its neighbour, declaring in a diplomatic note sent to Minsk in April that the sum aims to cover expenses Lithuania “suffered not only by keeping migrants, but also by strengthening our border control, infrastructure that we did not have”.

According to Moze, a Lithuanian border security guard in Lavoriskes, despite the erection of the fence and installation of inspection cameras, securing the country’s eastern border remains challenging.

Unmanned parts near lakes and forested areas continue to be potential entry points for migrants or a possible attack, he told Al Jazeera.

“The border has become more important since the war – we fear it could be used [by Russia] to attack our country or by Belarus to increase the influx of illegal migrants,” said Moze.

Lack of security

Although irregular migration across the Lithuania-Belarus border dramatically subsided since the start of the Russia-Ukraine war, feelings of insecurity among many Lithuanians living in border towns have not.

Standing next to her mother, Rozalija’s 39-year-old daughter Gintare is visiting for the weekend. For the past year, she has been working as a nurse in the capital, while her two brothers relocated to the coastal city of Klaipeda.

“It’s a mix of the war and migrants that’s ruined our lives,” Gintare told Al Jazeera. There’s no sense of security nor opportunities here.”

Until the war began, the three siblings lived in Barvoniskes. Since moving out, they take regular turns to check in on her their mother.

Regional threat

According to Tomas Janeliunas, professor of international relations at Vilnius University, the war on Ukraine has been “worrisome” for Lithuanians and citizens of other Baltic states previously invaded by Russia.

More recently, rumours that Belarus, Russian President Vladimir Putin’s biggest political and financial patron, started building camps for Russia’s Wagner mercenary group in its forests has ramped up regional worry.

“We feel a sharp threat from Russia because of our experiences over the centuries,” said Janeliunas, referring to previous Russian invasions.

“When Russia waged its war on Ukraine, it was our first call to be on the highest alert, invest in our defence and security, and gain the support of other NATO member states,” he added.

Vilnius hosted NATO’s two-day 2023 summit last week with the war on Ukraine and regional security topping the conference agenda.

“Lithuania [and other Baltic states] believe that if Ukraine were to fall, they would be next,” said Janeliunas. “That’s been a huge motivation for us to provide all the support Ukraine needs.”

Only the old

While many young people have left Lithuania’s border towns, many of the elderly remain despite feeling insecure.

“They said the fence will protect us, but we’ve felt less safe since the [Ukraine] war started,” said Domantas, a 73-year-old from the Lithuanian border town Vinziunai.

Holding hands with his wife of 50 years, Angelika, Domantas said: “Our children have all left [the town] but this is where we want to die.”

Like Domantas and Angelika, Lautius, a 70-year-old pensioner from the Lithuanian border town of Suskas, refuses to leave home and feels bitter about what the fence has done to his land.

“This fence has done nothing but take away my land from me,” said Lautius, explaining that it ate into his farmland and forced him to move away from his cattle.

“But whatever happens, I won’t leave my hometown,” he said.