WASHINGTON (AP) — The Pentagon is readying orders for the deployment of at least 1,000 additional active duty troops to bolster President Donald Trump’s expanding crackdown on immigration, U.S. officials said Friday.

They said roughly 500 more soldiers — largely a headquarters unit from the 10th Mountain Division at Fort Drum in New York — will be sent to the southwest border. And about 500 Marines will go to Guantanamo Bay, Cuba, where some of the detained migrants will be held.

The officials, who spoke on condition of anonymity because announcements have not been made, said there have been ongoing discussions about the deployments and the numbers could increase if additional details are worked out.

The Pentagon has been scrambling to put in motion Trump’s executive orders signed shortly after he took office on Jan. 20. The first group of 1,600 active duty troops deployed to the border last week.

The deployments reflect Trump’s determination to expand the military’s role in his campaign to shut down the border and send detained migrants back to their home countries.

Troops going to the border are expected to help put in place concertina wire barriers and provide needed transportation, intelligence and other support to the Border Patrol. Troops going to Guantanamo could help prepare the facility for an influx of migrants and do other support duties.