The Pentagon expects to soon receive a long-delayed formal request from the Department of Homeland Security (DHS) to host detention facilities for thousands of migrant families, The Daily Beast has learned.

Discussions are ongoing between the two departments, already collaborating with each other on a massive military mobilization at the southern border, officials said. It’s an effort that has prompted outrage and fears of troops firing on unarmed asylum seekers. Under discussion are the terms under which two military bases in Texas, the Army’s Fort Bliss and Goodfellow Air Force Base, will become detention sites for thousands of families.

The request is said to be imminent. But it’s unclear if it will come Friday, a source told The Daily Beast on condition of anonymity. At the Pentagon, a spokesman, Navy Capt. Bill Speaks, said, “We’ve still not received a request” from DHS.

“This is just another example of the politicization of DOD [the Department of Defense] and the use of DOD to carry out the kinetic component of an anti-immigrant propaganda campaign,” said Paul Yingling, a retired Army colonel and heralded Iraq veteran who has become increasingly outspoken against anti-immigrant fervor. “There is no legitimate reason to intern these families from a national security perspective. Instead, as with border operations, this internment is a political stunt. It fuels anti-immigrant hatred as part of the administration’s midterm electoral strategy.”

It is expected that Defense Secretary Jim Mattis will approve the request, as Mattis this week approved the deployment of 7,000 active and reserve troops to the U.S.-Mexico border—a force comparable to what’s currently in Iraq and Syria. Late Thursday, 104 House Democrats wrote to Mattis expressing “opposition” to what they called “nothing short of a militarization of the southern border to score political points and stoke misleading fears among Americans of immigrants.”

Internal bureaucratic preparation between the two agencies had been fallow, but it resumed in recent days, according to sources–around the time the administration’s focused turn to the migrant caravan. The caravan was in southwestern Mexico’s Oaxaca province as of Friday, about 870 miles from the Brownsville, Texas border.

In keeping with a plan that has been under discussion since the spring, the military would provide the space for the detention camps, but DHS would be in charge of conducting actual detention operations.

If approved, the plan would represent concrete implementation of what President Trump on Thursday called without detail the end of “catch and release,” an inflammatory and misleading depiction of immigrants’ legal rights to adjudicate their status in immigration courts.

“We're putting up massive cities of tents, the military is helping us incredibly well,” Trump said at the White House on Thursday.

Over the summer, both the Pentagon and DHS declined to provide basic information about the detention plans and the internal preparation for them. It is unclear what degree of access the bases will provide to attorneys, relatives and other advocates for thousands of migrants who would be unable to leave the camps on the bases. The Daily Beast accordingly filed a Freedom of Information Act request about the plan but the government has yet to produce relevant documents.

“ This is just another example of the use of DOD to carry out the kinetic component of an anti-immigrant propaganda campaign. ” — Retired Col. Paul Yingling

Seeking asylum is an internationally recognized human right and a legal right inside the United States.

An administration official first told the Washington Post on Thursday night that DHS had made the request, but the Pentagon’s Speaks denied that the Pentagon had actually received any formal entreaty from DHS to establish the camps. DHS representatives did not immediately respond to a request for comment.

While the Pentagon has emphasized the supporting role the military is playing at the border, Trump at the White House endorsed lethal force against a nonviolent, unarmed caravan of migrants using a hypothetical example of rock throwing. “They want to throw rocks at our military, our military fights back… I told them to consider it [a rock] a rifle,” said Trump, the commander-in-chief.

Firing on unarmed civilians is an unambiguous violation of military law. While several retired generals tweeted Thursday night that they doubted any soldier would follow the instruction of their commander-in-chief, Yingling feared that the atmosphere of incitement against immigrants risked violence.

“What I’m really worried about is that 19-year old who’s listening to this stuff about invaders and infestation. That young person is going to make a choice that will haunt them forever, because they’re hopped up on the hate-filled rhetoric,” he said. “That’s who I worry about–as well as the migrant families that are going to be on the receiving end of this brutality.”