Poland and Lithuania are considering closing their respective borders with Belarus amid concerns over the presence there of the Wagner mercenary group, a Lithuanian deputy interior minister said on Friday.

“The considerations are real. The possibility of closing the border exists,” Arnoldas Abramavicius told reporters.

Belarus has been hosting Wagner fighters following their short-lived rebellion against Russia’s top military brass.

Lithuania repeatedly warned its Western allies that Wagner mercenaries could disguise themselves as asylum seekers trying to cross Belarus’s borders with EU member states, or stage provocations involving refugees.

“It could be some groups of refugees, irregular migrants being transferred in order to cause some kind of unrest,” Abramavicius said.

Poland’s ruling party chairman Jaroslaw Kaczynski said on Friday that Wagner fighters “are not in Belarus for fun”.

“They are there to create various types of crises, primarily directed against Poland,” Kaczynski said, adding that Poland has been building up its defence capabilities “so that these provocations, these activities, fail”.

Both Poland and Lithuania erected fences on their borders with Belarus and Russia, accusing Minsk and Moscow of orchestrating migrant influxes into the EU in order to destabilise the bloc.