With only a few weeks' notice, the Lithuanian border guard service has turned a large prison in the southwest of the country into the country's biggest migrant centre.
At least 700 people will live in the so-called Kybartai Alien Registration Centre after it was renamed in late September.
The prisoners who were held there up until recently, have been relocated to other facilities around the country.
"Admittedly, it doesn’t sound good to put migrants in a prison," Arunas Kucikas, chairman of Caritas Lithuania, an international NGO, told Euronews.
"But considering the situation of Lithuania - that we didn’t have the infrastructure in place and weren’t prepared for such numbers - it is actually quite an improvement."
The Lithuanian government has been struggling to house around 4,200 migrants who have crossed its frontier with Belarus -- an outer EU border -- since May.
Vilnius accuses the government in Belarus of sending migrants -- many of them Iraqi -- to the border in a bid to destabilise the European Union. It is thought to be in retaliation for EU sanctions on Minsk over its crackdown on dissent following a disputed presidential election.
The migrants are helped to cross illegally into Lithuania, Latvia or Poland - and in some cases even forced by police officers with riot shields and weapons.
In response, the three EU nations that border Belarus -- Lithuania, Latvia and Poland -- have legalised so-called "push-backs", by which their border guard services force migrants back into Belarus.
Lithuania’s border guards claim they have pushed back more than 2.000 people since August. The arrival of new migrants has somewhat slowed after these measures and the EU negotiated with the Iraqi government to stop direct flights to Minsk.
However, both the situation on the border and housing of newly arrived migrants inside Lithuania has caused serious concern.
The hundreds of single men who will now stay in the Kybartai prison were living in tents for months in the village of Rudninkai. A caste system developed in the camp, according to the Lithuanian Red Cross, with some migrants preying on others by charging them to use bathrooms or even pushing people into prostitution. As of this month, the Lithuanian government says no migrants are living in tents anymore and that everyone has a roof over their heads.
"The prison in Kybartai is quite well equipped," Kucikas said. "There will be more privacy because less people share a room than before, there is heating, space to move around, exercise and get warm food."
Inside the prison, migrants are divided by nationality in sectors - "to avoid conflicts" according to the Lithuanian border guard. Each sector gets time slots to use the stadium, gym, library and other leisure areas. All sectors have their own basketball courts, fitness equipment and dining area.
The most vulnerable people, like women or families with children, will not be living in the former prison. They have mostly been brought to the capital Vilnius, where an old shelter centre for homeless people has been made available. "From what we can check, there are indeed no more people living in tents anymore," said Kucikas.
The next step will be to give the migrants something to do while they wait to have their asylum applications processed. A group of 200 children started learning Lithuanian recently. This is an important step because out of the 4,200 people who entered Lithuania, around 500 are children. A bigger problem, said Kucikas, is health care for more seriously ill people. Recently, a young child passed away in the migrant housing centre in Rukla in central Lithuania. Head injuries the child had sustained a long time ago had been left untreated and became fatal.
"This was a very tragic event," admits Kucikas. "We now really need to improve the migrants’ access to health care above the primary level. The good thing is that even though Lithuania might be struggling now, at least there is the will to make things better."