Concern is mounting that Vladimir Putin may escalate his war in Ukraine by sending in troops from the east and west of the Suwalki Gap, cutting off the Baltic States from the rest of NATO. Previously dubbed “NATO’S Achilles heel” and “the most dangerous place on Earth”, the Suwalki Gap stretch of land between Poland and Lithuania is also the shortest land route between the Russian state of Kaliningrad and Moscow’s faithful ally Belarus.Given his struggle to make headway in Ukraine, there are fears Putin would ramp up war efforts by sending in forces from Kaliningrad and Belarus to isolate Estonia, Latvia and Lithuania from the rest of NATO.Linas Kojala, director of the Eastern Europe Studies Centre, told Sky News: “The Suwalki Gap is a potential vulnerability as Kaliningrad and Belarus – now basically a military extension of Russia – could try to cut the Baltic States off from Poland.”Vistytis is a Lithuanian town situated just over the border from Kaliningrad in the south west of the country.For the townspeople, Russia’s presence is a constant threat that they have had to become accustomed to. There are fears Russia may send troops into the Suwalki Gap (Image: Getty) Belarussian President Alexander Lukashenko (Image: Getty)Former military medic, Vilius Kociubaitis, who is now the town’s doctor, said: “We hear helicopters, maybe the tanks shooting.”Some residents have packed up their cars ready to flee to their larger, more protected neighbour Poland.Mr Kociubaitis added: “We are afraid because if Ukraine falls, we have a big problem because the Russians will come to us from Kaliningrad and also from Belarus.READ MORE: Truss ‘obsessively’ checking weather charts in her final days as PM The Suwalki Gap runs between Lithuania and Poland (Image: Sky News) Vilius Kociubaitis (Image: Sky News)”It’s a big risk.”Earlier this month Belarus announced that around 9,000 Russian troops will be posted to the country as part of a “regional grouping” of forces.Over 8,000 Lithuanian volunteers have already signed up to join militia group The Riflemen’s Union, while others have fought for the foreign legion in Ukraine.DON’T MISS:Jair Bolsonaro narrowly loses to left-wing candidate Lula da Silva [LATEST]Man attacks Dover migrant centre by ‘hurling petrol bombs’ [REPORT]Prince Harry’s memoir branded a ‘time-bomb’ for the Royal Family [REVEAL] Mindaugas Lietuvninkas (Image: Sky News)Mindaugas Lietuvninkas spent the spring fighting the Russians around Irpin and is now in training preparing to return.He remembers life under Soviet rule in Lithuania and has vowed it should never return.He said: “They [the Russians] want to come back, but they will not come back, at least I will be one of those who will not let them come here.”