Hundreds of Texas National Guard soldiers are on the border and are now authorized to arrest migrants.

Soldiers were previously not allowed to detain or search migrants, they were only allowed to report what they saw to nearby agents.

If they want to make an arrest, a Border Patrol agent will have to supervise them.

On Military Highway in western Hidalgo County, an area that once saw thousands of migrant crossings a month, is now quiet. 

Despite the drop in crossings, hundreds of Texas National Guard troops were recently deployed to the Rio Grande Valley. They're now working alongside Border Patrol agents.

In an agreement between Governor Greg Abbott and U.S. Customs and Border Protection, troops are now allowed to arrest migrants who cross the border illegally.

"You know entries are down, but we have to also speculate what could happen tomorrow," Border Patrol RGV Sector spokesperson Andres Garcia said.

If soldiers do make an arrest, a Border Patrol agent will have to supervise them.

Garcia says this doesn't have to be done in person. 

"The radios, you know, we can communicate with each other, but most of the times, they're real close to an agent," Garcia said.

Though soldiers will soon be able to arrest people who cross the river, their role will likely be more stationary, like at the border wall. Border Patrol says this will free up some of their agents.

"If an agent is assigned to man up the camera or conduct a certain aspect, like a stationary point by the wall, that frees up the agent to go out in the field and conduct the regular duties," Garcia said.

Troops are currently undergoing trainings on Title 8. That's the decades-old law that outlines immigration law and processes.

They will have to finish that training before making any arrests on the border. 

ACLU Senior Staff Attorney Edgar Saldivar says they're concerned about troops enforcing immigration law. He says it can lead to racial profiling in border communities and beyond.

"What's to stop them from not sticking to the border regions and extending into other corners of the state?" Saldivar said.

Saldivar feels the authorization on top of Operation Lone Star and deploying new troops is a 'militarization' of the border. 

He also says the ACLU will be keeping an eye on how soldiers enforce Title 8.

The 400 troops from North Texas will be stationed throughout the RGV sector's nine stations.

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