The Federal Bureau of Prisons is assisting the Border Patrol with the transport of migrants, according to sources.
Multiple Border Patrol sources told Fox News that the Federal Bureau of Prisons is assisting in transporting migrants, since Customs and Border Protection/Border Patrol are overwhelmed in several areas.
A spokesperson for the Federal Bureau of Prisons told Fox News the agency "is providing limited transportation resources to assist Border Patrol on the southwest border."
It comes as the U.S. southern border saw a new record in the number of migrant encounters in a single day, with 12,600 encounters taking place on Monday.
The number doesn't include thousands of migrants who are waiting for processing in the Del Rio Sector on Monday evening.
Sources told Fox News that, as of Tuesday morning, over 4,500 migrants were at the busy crossing point, while more than 5,300 were in custody.
Officials with the Department of Homeland Security told lawmakers in December that there were around 670,000 "gotaways," known as illegal immigrants who slipped past border agents, in FY 23.
ARIZONA'S DEMOCRATIC GOV MOBILIZES NATIONAL GUARD TO BORDER, AS WASHINGTON TRIES TO REACH DEAL
Arizona's Democratic Gov. Katie Hobbs announced Friday she's deploying the state's National Guard to help.
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"With this Executive Order, I am taking action where the federal government won’t. But we can’t stand alone, Arizona needs resources and manpower to reopen the Lukeville crossing, manage the flow of migrants, and maintain a secure, orderly and humane border," Hobbs wrote in a statement.
Fox News' Adam Shaw, Bill Melugin and Griff Jenkins contributed to this report.