President Donald Trump has placed a 60-foot-wide strip of land along the US-Mexico border under the jurisdiction of the US military, a move aimed at continuing the White House’s efforts to deter illegal immigration.

Trump issued an order authorizing the temporary military control of the Roosevelt Reservation, a federally owned stretch of land established in 1907 by President Theodore Roosevelt for the purpose of border security. The strip spans parts of California, Arizona, and New Mexico. Under the order, military personnel will be permitted to detain individuals who cross into the US illegally within this area.

According to a report by Politico, Trump had previously authorized military operations on the Roosevelt Reservation during his first term to assist with the construction of the border wall. The order is part of a broader effort by President Trump to increase military involvement in addressing mass illegal immigration at the southern border.

“Our southern border is under attack from a variety of threats,” the order stated.  “The complexity of the current situation requires that our military take a more direct role in securing our southern border than in the recent past.”

The directive, however, has raised concerns from critics who argue it may violate the Posse Comitatus Act, a federal law that prohibits the use of active-duty military personnel for domestic law enforcement purposes.

“Welp they’re doing the Roosevelt Reservation crazy strategy, giving the military ‘jurisdiction’ over a 60-foot-wide stretch of land from CA to AZ and then claim that migrants are being arrested for ‘trespassing on military property’ thus trying to bypass the [Posse Comitatus Act],” wrote Aaron Reichlin-Melnick, a senior fellow at the American Immigration Council, in a post on X. The Trump administration has argued that by placing the land under the jurisdiction of the military, active-duty troops can detain illegal immigrants the same way they would temporarily detain a trespasser on a military base until law enforcement arrives.

The order also directed the Departments of Defense and Homeland Security to submit recommendations by next week on whether Trump should invoke the Insurrection Act of 1807 to support deportation efforts. The law would allow the president to deploy additional military forces to the southern border and allow them to assist law enforcement.

Illegal border crossings have dropped significantly since Trump took office. The administration reported just 7,200 migrant encounters in March, a stark decline from over 189,000 recorded during the same month last year under the Biden administration.