The order would empower troops to detain people attempting to illegally enter the U.S. within the stretch of land, which was established by President Theodore Roosevelt for border security in 1907. Trump authorized the military to operate in the same area during his first administration to aid construction of a wall to deter migrant crossings.

The U.S. Department of Defense is now in charge of securing the country's southern border, having been granted new powers to enforce security there by President Donald Trump.