Five immigrants deported by the United States to the small southern African nation of Eswatini under the Trump administration’s secretive third-country program are in prison, where they will be held in solitary confinement for an undetermined time.

The migrants—citizens of Vietnam, Jamaica, Cuba, Yemen, and Laos—had served prison sentences in the U.S. for serious crimes, according to the Department of Homeland Security (DHS). Homeland Security Assistant Secretary Tricia McLaughlin described the five men as "individuals so uniquely barbaric that their home countries refused to take them back."