This is a published rule of Belorussian airspace. If there is a terrorist threat onboard a plane in it the plane cannot leave the airspace and must land in Bela

This is a published rule of Belorussian airspace. If there is a terrorist threat onboard a plane in it the plane cannot leave the airspace and must land in Belarus. I don’t know if this is a common rule or not. Maybe it was intentionaly established for situations like this?