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

It was not immediately clear what units and service branches would be tapped for the deployment, but the announcement comes amid the Trump administration's executive actions directing a comprehensive military border mission.

The Pentagon is sending at least 1,500 active-duty troops to the southern border to enhance security and assist with a major military airlift of undocumented migrants.