The Pentagon said Wednesday it has begun deploying 1,500 active duty troops to help secure the southern border in the coming days, putting in motion plans President Donald Trump laid out in executive orders shortly after he took office to crack down on immigration.

A briefing document provides an early glimpse into the practical application of Trump’s executive orders on immigration and the border.

The Trump administration has essentially eliminated the ability to pursue asylum at the border, attempting to erase by executive order a right established in U.S. and international law. The restrictions leave migrants who claim they fear for their lives almost no path toward safety in the United States.

Federal agents are investigating after a US Border Patrol agent was shot and killed Monday afternoon on the highway in Vermont.