Dozens of Marines are now stationed at a Border Patrol station in eastern San Diego County, a new development that points to the Trump administration’s military buildup on the southern border.
Some Marines there told CalMatters on Wednesday that they are out in Campo patrolling the border twice a day.
That’s a change from how Marines have operated in Southern California since President Trump took office. Until now, Marines have been limited to a supporting role, adhering to the Posse Comitatus Act of 1878, which keeps the armed forces away from civilian law enforcement.
But Trump has long hinted at using the armed forces in unprecedented ways at the border to deal with what he describes as “an invasion.”
And recently, the Trump administration shifted immigration enforcement northward toward the interior of California. Border Patrol agents have been seen chasing farmworkers through strawberry fields in Oxnard and swarming workers in unmarked cars at bus stops in inner-city Los Angeles.
The Marines have not disclosed detaining anyone in California. Active-duty Army soldiers patrolling the border in New Mexico earlier this month reported turning people over to immigration authorities, a change that illustrated escalating immigration enforcement by military service members.
A spokesperson for the Joint Task Force Southern Border, in charge of the operation, did not return a request for comment. Border Patrol Agent Gerardo Gutierrez said the Marines “are just staging there for their assistance along the border,” and gave no further details.
California officials and immigration experts do not have details on what the Marines are doing at the border.
“It’s not clear to me what instructions the Marines are being given with respect to engagement with people who are attempting to cross the border,” said Kevin Johnson, a UC Davis School of Law professor whose work focuses on immigration and civil rights.
In April, Trump declared a 60-foot-wide strip of federal land that runs the length of the entire border as a “military installation,” a status meant to allow troops to patrol the region in the same way they protect military bases.
On a recent trip to the Border Patrol site in Campo, CalMatters reporters observed Marines’ olive-colored tents pitched atop hot asphalt with nearby water tanks for brushing teeth and washing. They have a pile of MREs, or “meals-ready-to-eat,” for food.
Their camp is a couple of hundred yards from the start of the Pacific Coast Trail — a stone’s throw from the U.S.-Mexico border. The area is very remote.
Newsom sued to stop LA deployments
Earlier this month, Gov. Gavin Newsom clashed with Trump over the federalization of the National Guard in Los Angeles and deployment of U.S. Marines to subdue protesters, calling it “an unmistakable step toward authoritarianism.” Newsom sued the administration, but a panel of judges from the 9th Circuit Court of Appeals ruled the president had followed the law and the case is unfolding at a lower court.
A spokesperson for Newsom in a written statement to CalMatters connected the Marines at Campo to the Trump administration sending Border Patrol agents hundreds of miles inland.
“We believe in strong border security, but this campaign is not about security—it’s about fear,” said Diana Crofts-Pelayo of Newsom’s office.
“Now it appears Marines are being forced to backfill those border slots,” she continued. “This is not just mission creep—it’s putting law enforcement, our soldiers, and the community in danger.”
The military presence in Campo, previously unreported, follows an earlier deployment of roughly 500 Marines from Camp Pendleton, who had been positioned in the small coastal town of Imperial Beach and in an inland border area near Brown Field Airport in Otay Mesa. According to the Department of Defense, those troops are tasked with “detection, monitoring, logistics, and transportation support along the border.”
Over the last three decades, the border has become one of the most militarized regions in the world, with stronger, more formidable, and taller border barriers and increased surveillance. Migrant deaths have increased as people sought more dangerous routes in the U.S., the Mexican government reported last month.
How Trump’s border mission differs from others
When he took office, Trump issued a series of executive orders, including a national emergency declaration, to achieve what he described as “full operational control” of the southern border. The orders directed the Department of Defense, through U.S. Northern Command, to bolster border enforcement through increased military involvement.
Some legal experts say turning land along the border into a “military installation” may sidestep the Posse Comitatus Act, which typically bars federal armed forces from conducting domestic law enforcement.
“There’s a concern that armed troops may use deadly force in situations and that people may be injured,” said Johnson, adding that military forces don’t have experience dealing with vulnerable migrants, and it’s not clear what training they’ve received.
“It’s like a ticking time bomb,” he added. “I hate to say it this way, but it’s only a matter of time until we see something bad happen.”
This isn’t the first time U.S. troops have been sent to the border. The Department of Defense has deployed troops to the border under both Republican and Democratic administrations for construction and surveillance. But until now, their role has been limited to conducting surveillance, repairing vehicles, and fortifying barriers.
The latest wave of deployments brings the total number of military personnel supporting the Border Patrol’s mission at the Mexico border to more than 10,000 – adding to the approximately 2,500 who were already stationed along the entire length of the 2,000-mile border. The number of troops at the border fluctuates as the units rotate and additional forces are mobilized, according to the Defense Department.