The United States sent five immigrants it says were convicted of serious crimes to the African nation of Eswatini, the U.S. Department of Homeland Security said — an expansion of the Trump administration's largely secretive third-country deportation program.

On board the flight were five deportees from Vietnam, Jamaica, Laos, Cuba and Yemen who have been convicted of crimes ranging from child rape to murder, US Homeland Security Department Assistant Secretary Tricia McLaughlin said in an online post.

The US has reportredly deported five convicted criminals to Eswatini in a secretive expansion of its third-country deportation program, raising local and international concerns.