WASHINGTON — The Pentagon said on Wednesday that it would build temporary housing along the southwestern border for 7,500 migrant adults facing deportation, the latest step in the administration’s efforts to respond to a surge of undocumented immigrants and asylum seekers trying to enter the United States.
The Defense Department will loan military-style tents to the Department of Homeland Security, Pentagon officials said. In a statement emailed to reporters, Maj. Chris Miller, a Pentagon spokesman, said that military personnel would only set up the tents and that the operation of the facilities would rest with homeland security.
The cost for putting up the tents — to be constructed near Tucson, as well as near Tornillo, Donna, Laredo and Del Rio, Tex. — will be determined after the Pentagon conducts on-site assessments over the next two weeks.
Detention centers at the border have been pushed to overcapacity as an increase of migrants, most of them from Central America, have crossed into the United States. Officials recently said they would spend millions on the construction of tent cities in Texas, and they also began flying migrants to facilities with more space in Del Rio, Tex., and in California.
Defense Department officials said that the acting defense secretary Patrick Shanahan approved the request for assistance that the Department of Homeland Security made on May 9.
A day after receiving that request, Mr. Shanahan notified Congress that he intended to shift $1.5 billion that had been designated for the war in Afghanistan and other projects to help pay for work on Mr. Trump’s border wall.
At the time, Mr. Shanahan, who is expected to be nominated as defense secretary, said that the money from the Pentagon’s other programs would be the last that it moves to help build about 80 miles of fencing and barriers along the southwestern border. That shift was in addition to the $1 billion that the Defense Department transferred to wall construction in March from the Army’s personnel budget.
Mr. Shanahan’s acquiescence to the president’s efforts to use the military along the border is likely to affect what was already expected to be a contentious confirmation battle. Many Democratic lawmakers view the border wall as unnecessary and have expressed concerns about the increasing use of the military to help in the president’s crackdown on undocumented immigrants and asylum seekers trying to enter the country.
Since Mr. Trump declared what he called a national security crisis at the border that warranted the deployment of active-duty troops, some officials at the Defense Department had sought to limit their role. But the administration has kept them in the mix.
The Posse Comitatus Act, dating to Reconstruction, bars American forces from engaging in law enforcement activities within the borders of the United States.
In recent months, homeland security has also diverted to the border officials who provide security elsewhere in the country. The department has requested volunteers from agencies like the Transportation Security Administration, the Federal Emergency Management Agency and the Coast Guard to assist with processing migrants at the border.
Customs and Border Protection officials in April detained 109,144 migrants at the southwestern border, including at its legal ports of entry, the highest total since 2007.