Thousands more service members have been put on standby for possible deployment to join the 5,200 active-duty troops being sent to the southern border this week to help federal agents stop what President Donald Trump has called an "invasion" by a caravan of migrants and political asylum seekers.
"Several thousand" additional troops have been put on notice that they also could be sent to the U.S.-Mexico border if necessary, Stars and Stripes reported Tuesday, citing an anonymous defense official.
Announcing the deployment of the 5,200 troops Monday, Air Force Gen. Terrence O'Shaughnessy, commander of U.S. Northern Command, said, "Our concept of operations is to flow in our military assets with a priority to build up southern Texas and then Arizona and then California" to back up the efforts of U.S. Customs and Border Patrol (CBP) "to harden and secure the border."
About 800 troops from Fort Knox and Fort Campbell in Kentucky would be the first of the active-duty troops to deploy and be sent to Texas, he said. But it was not immediately clear whether they had already arrived. All 5,200 should be in place by Saturday, he added.
The active-duty troops will join about 2,000 from the National Guard who have been on the border since April and will be guided by much the same federal rules, which bar them from detaining anyone or carrying out any law enforcement activities.
O'Shaughnessy stressed that all the troops are in a support role for CBP under the "posse comitatus" law, which generally prohibits the military from civilian law enforcement, according to the Stars and Stripes report.
CBP Commissioner Kevin McAleenan said the troops will serve as a deterrent to the estimated 3,500 mostly Central American migrants in the so-called "caravan," which is still nearly 1,000 miles from the border, according to The Associated Press.
"I think part of the goal is to deter people from trying to cross between ports of entry," said McAleenan, who joined O'Shaughnessy at a news conference Monday. "[The caravan] is near the Chiapas-Oaxaca border in southern Mexico. We're also aware of a second large group of migrants at the Ciudad Hidalgo border crossing between Guatemala and Mexico."
In rallies leading up to the Nov. 6 midterm elections, Trump has repeatedly stressed the immigration issue and warned that "lots of bad people" -- possibly from the Middle East or members of the Salvadoran MS-13 gang -- may have infiltrated the caravan, although he acknowledged last week that he had no proof.
On Fox News' Laura Ingraham program Monday night, Trump said, his efforts had "nothing to do" with the midterm elections.
But retired Army Lt. Col. Jason Dempsey called the deployment "an October, or maybe a November, surprise" that amounts to a "political stunt."
"This is wasting soldier time, wasting taxpayer money," said Dempsey, who served tours in Iraq and Afghanistan and is an adjunct senior fellow of the Military, Veterans, and Society Program at the Center for a New American Security.
In a phone interview with Military.com, Dempsey questioned why active-duty troops are needed for the strictly limited support and surveillance roles that could be carried out by the National Guard, and are already being performed by Guard troops sent to the border in April.
This story will be updated.
-- Richard Sisk can be reached at richard.sisk@military.com.