About 800 U.S. soldiers assigned to Operation Faithful Patriot will be in San Antonio by the end of Tuesday. They're staging at Joint Base San Antonio Fort Sam Houston before being deployed to the Texas-Mexico border.
That's according to ABC News’ Luis Martinez who is reporting from the Pentagon.
The troops from Fort Campbell and Fort Knox in Kentucky began arriving Monday night.
They're the first wave of 5,200 troops assigned to assist the Border Patrol.
More troops are expected to stage at Davis-Monthan Air Force Base in Tucson, Arizona, and at Marine Corps Base Camp Pendleton or Marine Corps Air Station Miramar in California.
Operation Faithful Patriot has been described as an effort to help protect the border from migrants trying to cross into the country illegally or seeking asylum. The troops are expected to focus first on the Texas border and then Arizona and California.
Democrats have criticized the military operation, calling it a political tactic ahead of the midterm elections.
On Tuesday, U.S. Rep. Joaquin Castro (TX-20) released the following statement about the deployment:
As part of a continuous effort by this Administration to demonize immigrants, the President has now announced that he will deploy additional military to the Southern border in response to migrants fleeing Central America. Given this group of migrants is over a thousand miles away, this is a tactic used to instill fear among the American people, undermines the readiness of the military, and is a waste of federal resources as the National Guard is already deployed to the border. The President should let the military defend against actual threats instead of those manufactured to divide our nation.
President Donald Trump has said the effort to secure the border has nothing to do with elections.
Read more about Operation Faithful Patriot here.
Video of troops landing at Kelly Field on Sunday provided by Defense Visual Information Distribution Service: