An initial wave of 1,600 troops was deployed to the U.S.-Mexico border by Monday following a mobilization that started last week.
The border mission has become the Defense Department's top priority as Defense Secretary Pete Hegseth also entered the Pentagon for the first time Monday after being confirmed by an unusually close Senate vote late Friday. And the 1,600 may likely be just the beginning as President Donald Trump eyes a historic crackdown on immigration.
"Whatever is needed at the border will be provided," Hegseth assured reporters Monday, hinting at the possibility of additional deployments in the coming weeks.
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Defense officials confirmed to Military.com that the 82nd Airborne Division's 3rd Brigade Combat Team, out of Fort Liberty, North Carolina, has been preparing for mobilization since last week, as well as elements with the Fort Drum, New York-based 10th Mountain Division.
The bulk of deployed troops come from the Army, primarily military police, to enhance surveillance efforts and act as a deterrent to illegal crossings along the border with Mexico. Simultaneously, roughly 500 Marines specializing in engineering are repairing and reinforcing physical barriers along the border.
They join some 2,500 National Guard and Army Reserve troops who were already there. A senior Guard official has been appointed as a liaison coordinating troops in concert with Trump's new border surge. The National Guard Bureau on Monday refused to identify the official.
"We are trained and ready to support this important mission," Lt. Col. Phillip Mason, 716th Military Police Battalion commander, said in a statement. "Our soldiers are committed to protecting all Americans and supporting our civilian partners in defending the territorial integrity of the United States."
Here is a list of the military units that are already at the border per Trump's orders.
Active-duty Army units on the border mission:
- Headquarters, 89th Military Police Brigade, Fort Cavazos, Texas
- Headquarters, 720th Military Police Battalion, Fort Cavazos, Texas
- 401st Military Police Company, Fort Cavazos, Texas
- 202nd Military Police Company, Fort Bliss, Texas
- Headquarters, 716th Military Police Battalion, Fort Campbell, Kentucky
- 23rd Military Police Company, Fort Drum, New York
- 549th Military Police Company, Fort Stewart, Georgia
- 530th Combat Engineer Company-Armored, Fort Stewart, Georgia
- 977th Military Police Company, Fort Riley, Kansas
- 41st Combat Engineer Company-Armored, Fort Riley, Kansas
- 569th Combat Engineer Company-Armored, Fort Carson, Colorado
- Headquarters, 759th Military Police Battalion, Fort Carson, Colorado
- 66th Military Police Company, Joint Base Lewis-McChord, Washington
Active-Duty Marine Corps units on the border mission:
- Detachment from 1st Combat Engineer Battalion, 1st Marine Division, Camp Pendleton, California
- Detachment from 7th Engineer Support Battalion, 1st Marine Logistics Group, Camp Pendleton, California
The Air Force -- with a major assist from the Coast Guard -- was also playing a role in the border operation, with C-17 Globemaster III and C-130 Hercules aircraft participating in repatriation flights, meaning they are flying undocumented migrants back to their countries of origin. However, the Air Force has declined to specify which units are involved, unlike the other services.
Images and photo captions posted publicly on the Defense Visual Information Distribution Service show Air Force C-17 Globemaster III aircraft assigned to the 62nd Air Wing at Joint Base Lewis-McChord, as well as the 60th Air Mobility Wing assigned to Travis Air Force Base in California. A C-130 Hercules was also pictured arriving at Biggs Army Airfield at Fort Bliss, Texas.
Some of those military flights were initially rejected by other countries. Colombia's President Gustavo Petro decried the military efforts in a social media post on Sunday, but caved to Trump's demands shortly afterward.
"A migrant is not a criminal and must be treated with the dignity that a human being deserves," Petro wrote on X. "That's why I turned back the U.S. military planes that were carrying Colombian migrants."
Trump threatened Colombia with tariffs if it didn't accept the flights. A White House press statement on Sunday said Petro agreed to the military flights "without limitation or delay" following those threats.
Meanwhile, the Coast Guard began flying detained migrants "of various nationalities" to Laredo, Texas, and San Diego on Jan. 25 for deportation.
The service would not provide Military.com with the number of flights it has conducted or the number of migrants it has transported. A statement provided to Military.com on Monday only referenced the flights that took place on Saturday.
"The Coast Guard is surging assets and personnel from around the nation -- including Air Stations Elizabeth City, Kodiak, Sacramento, San Diego, and Hawaii -- to support this Department of Homeland Security-led operation," a Coast Guard official said in the statement.
The Coast Guard's Eleventh District is coordinating the flights, according to the service. Adm. Kevin Lunday, the service's acting commandant, said Saturday that the Coast Guard is drawing on its unique capabilities to "protect America's borders, territorial integrity, and sovereignty."
"Today's operation exemplifies our coordination with our Department of Homeland Security and Department of Defense teammates, through which we are detecting, deterring, and interdicting aliens, drug smuggling, and other terrorist or hostile activity before it reaches our border," Lunday said in a news release.
The move follows a Coast Guard announcement last week that it plans to send additional cutters, aircraft, boats and specialty teams for surge operations off the Florida coast to deter migrants traveling from Haiti and Cuba as well as the Gulf of Mexico -- which the service called the "Gulf of America" in its release per a pronouncement Jan. 20 by Trump that he was renaming the body of water between the southern U.S. and Mexico.
The Coast Guard also is sending additional assets to the U.S. territories in the Pacific as well as Puerto Rico and the U.S. Virgin Islands as part of the surge.
Lunday has served as acting commandant since Jan. 21, after Coast Guard Commandant Adm. Linda Fagan was fired by the Trump administration -- the first high-profile dismissal since Trump took the oath of office Jan. 20 -- for reasons that included "leadership deficiencies, operational failures, and inability to advance the strategic objectives of the U.S. Coast Guard," according to a Department of Homeland Security statement provided to Military.com.
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