and ed , ▁some ▁travel ers ▁also ▁encountered ▁issues ▁with ▁their ▁vis as ▁after ▁arriv ing ▁at ▁destin ations ▁unexpected ly : ▁ ▁At ▁Br uss els ▁air port , ▁ 2 0 0 ▁travel ers ▁from ▁Bang l adesh ▁were ▁unable ▁to ▁leave ▁the ▁building ▁without ▁a ▁vis a . ▁ ▁Pass engers ▁from ▁Kol k ata ▁head ed ▁for ▁London ▁on ▁an ▁Air ▁India ▁flight ▁were ▁di vert ed ▁to ▁Frankfurt , ▁where ▁they ▁were ▁unable ▁to ▁leave ▁the ▁air port ▁to ▁seek ▁accommod ation ▁because ▁they ▁did ▁not ▁have ▁vis as ▁for ▁Germany . ▁ ▁A ▁group ▁of ▁passengers ▁from ▁the ▁United ▁Kingdom ▁were ▁facing ▁arrest ▁in ▁Del hi ▁over ▁a ▁bre ach ▁of ▁imm igration ▁laws , ▁because ▁they ▁left ▁the ▁air port ▁without ▁vis as . ▁ ▁On ▁ 1 7 ▁April ▁the ▁UK ▁Border ▁Agency ▁announced ▁that ▁it ▁would ▁make ▁allow ances ▁for ▁trav ellers ▁who ▁were ▁unable ▁to ▁leave ▁the ▁UK ▁and ▁whose ▁vis as ▁had ▁exp ired , ▁provided ▁that ▁evidence ▁of ▁travel ▁res erv ations ▁during ▁the ▁travel ▁dis ruption ▁was ▁presented . ▁Bel arus , ▁Ser bia , ▁Finland , ▁and ▁Russia ▁also ▁e ased ▁vis a ▁formal ities ▁for ▁affected ▁passengers . ▁ ▁Altern ative ▁transport ▁routes ▁ ▁Pass engers ▁dest ined ▁for ▁countries ▁where ▁air space ▁was ▁closed ▁had ▁to ▁switch ▁to ▁other ▁modes ▁of ▁transport , ▁possibly ▁via ▁air ports ▁still ▁open ▁in ▁Portugal , ▁Mor oc co , ▁and ▁Turkey ▁to ▁the ▁east . ▁Once ▁inside ▁Europe , ▁many