Pedestrians pass troops placing razor wire at border with Mexico, McAllen, Texas, November 2, 2018 (Eric Gay/AP)

The Pentagon has rejected a law enforcement role for 5,200 troops ordered by Donald Trump to the border with Mexico.

As part of his anti-immigrant campaign before Tuesday’s Congressional elections, Trump insisted on the deployment against a migrant caravan which includes women and children and is still six weeks away from the border. He has said he might raise the deployment to 15,000 — greater than the US presence in Afghanistan — and said that troops can fire on anyone throwing rocks, a statement rejected by military commanders.

Trump insisted on Friday that soldiers can arrest those crossing the border, part of the Administration’s “zero tolerance” policy which has split families and is seeking to prevent asylum claims:

If our soldiers…are going to be hit in the face with rocks, we’re going to arrest those people. That doesn’t mean shoot them. But we’re going to arrest those people quickly and for a long time.

EA on talkRADIO: Funny Money in Brexit Vote; UK Minister Resigns; Trump v. Decency
TrumpWatch, Day 651: Trump — Troops Can Shoot Migrants Throwing Rocks

“Two defense officials familiar with the request” said the Department of Homeland Security asked the Pentagon to provide a reserve force that could provide “crowd and traffic control” and safeguard Customs and Border Protection personnel at the border.

The Pentagon rejected the request on October 26, but agreed to provide DHS with air and logistics support, medical personnel, and engineers.

Defense officials have repeatedly emphasized that troops support civil authorities and are not expected to come into any contact with migrants.

Active-duty troops are barred from domestic law enforcement unless there is an emergency.

One defense official said that the Defense Department told DHS that if it want the reserve force, it must ask the White House to formally grant the Pentagon the authorities to perform additional functions.

Retired Gen. Martin Dempsey, the Chairman of the Joint Chiefs of Staff from 2011 to 2015, condemned the deployment — with an estimated initial cost of $50 million — on Thursday: