Active duty military troops will begin arriving in El Paso, Texas, and San Diego on Thursday evening, in what defense officials said is the first batch of the new forces being deployed to secure the southern border.

U.S.-Mexico border for a deployment that includes the use of military aircraft to conduct deportation flights and support for construction efforts to extend the wall that separates the two countries.

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