The first planeload of criminal migrants has arrived at Guantanamo Bay in Cuba, where a small migrant detention center is being expanded to house tens of thousands. A Department of Homeland Security source told The Post that the detainees are “highly dangerous” illegal migrants.

As tents went up in Guantanamo Bay, Cuba to hold migrants, attorneys at the Department of Homeland Security and Pentagon were still trying to determine whether it was legal to take the unprecedented step of flying migrants from the US southern border to the facility,