The United States has cleared out the last migrants being held at its naval base at Guantanamo Bay, Cuba, sending them back to the U.S. mainland as they await deportation.

Trump announced plans to open a detention center at Guantanamo Bay to house up to 30,000 migrants. So far it can hold 225

U.S. immigration and military authorities disclosed Monday that immigrants from 27 countries were being held at Guantanamo Bay Naval Station in Cuba, while revealing new details of conditions of confinement and defending the government's authority to transfer and hold immigrants at the military base.