US Army soldiers move to another location near the US-Mexico border on November 3, 2018 in Donna, Texas.
CNN  — 

Active duty troops on the southern border with Mexico began carrying out “welfare checks” on detained migrants earlier this month to help out overwhelmed Customs and Border Protection agents, two US defense officials have told CNN.

The news comes as the Pentagon confirmed that it had approved a request Tuesday night from the Department of Homeland Security to authorize and fund an additional 1,000 National Guard troops to be deployed in support of CBP agents on border. Those National Guard forces will be under the command of Republican Gov. Greg Abbott of Texas.

“Active duty DOD military personnel are assisting Customs and Border Protection agents in CBP facilities by periodically monitoring migrant well-being, and reporting suspicious, violent, or medically related unresponsive behavior,” one of the officials told CNN.

If they observe such activity, US troops are then supposed to notify CBP personnel who would take over the handling of the situation from that point.

The new welfare role for troops marks a departure from their original mission on the border and is raising questions about the nature of the military’s role as the Trump administration faces criticism about the conditions of the facilities migrants are being housed in.

When US troops were first deployed to the border to support CBP agents, Pentagon officials stressed that military personnel would not be in ‘direct contact” with migrants.

Welfare checks primarily happening in Texas and Arizona

The welfare checks are primarily happening at CBP border patrol stations in Texas and Arizona. Because CBP is in need of the extra help, troops are conducting tasks that are bringing them into closer proximity with migrants and direct interactions are increasing.

An April request from CBP to the Defense Department for help dealing with the humanitarian crisis led to the welfare checks becoming an approved task for US troops.

That particular ask included a request for troops to assist with “monitoring the welfare of individuals in CBP custody,” according to a Pentagon statement at the time. Officials are now detailing what those welfare checks involve. There are about 350 troops that may at any time be involved in this effort.

US troops already help transport migrants and prepare and distribute meals at some locations. It’s not clear to what extent troops are receiving additional medical training to judge if migrants are unwell.

A CBP spokesman confirmed that the military is carrying out wellness checks and preparing food.

Troops may also be called upon to monitor overall conditions including ensuring air conditioning is working properly, according to one official.

Separately for several months military medical personnel have been stationed in the border area to treat troops who may become ill but are also on standby for migrant medical emergencies.

The troops involved in the border mission are carrying cards with basic Spanish language expressions to help them communicate with the migrants.

National Guard deployment

Of the 1,000 additional National Guard troops being deployed the majority of the additional personnel that are being sent will be involved in assisting CBP as it operates the “adult migrant holding facilities.”

The Department of Homeland Security will provide “mission specific training” for the Texas National Guard personnel, according to a statement by Pentagon spokesman Maj. Chris Mitchell.

Approximately 750 of the National Guard personnel will “provide supplemental holding support to CBP at CBP’s temporary adult migrant holding facilities in Donna, Texas and Tornillo, Texas,” Mitchell said, adding that they “will assist DHS law enforcement personnel with operational, logistical, and administrative support.”

“Migrants will be supervised by DHS law enforcement personnel,” he added.

The remaining 250 Texas National Guard members will provide support at CBP-designated ports of entry and airports in Texas “to enhance border security and improve the flow of commercial traffic.”

The Defense Department also announced that an additional 1,100 active duty military personnel will be deployed to the border in order to help make-up a shortfall in available National Guard personnel.

“Active Duty force deployments will increase in the next several weeks by approximately 1,100 personnel in support of CBP’s Operation Guardian Support mission with aerial surveillance, operational, logistical, and administrative support,” Mitchell said.

“The Active Duty force will be providing back-fill” to CBP “due to a shortfall in volunteer National Guard personnel,” he added.

Several governors, including the governors of multiple border states, had previously announced that they would not allow their respective National Guard forces to participate in the CBP border mission, potentially explaining the absence of available personnel.

Both new deployments were approved by acting Secretary of Defense Richard Spencer, who stepped into his role on Monday after his predecessor Mark Esper stepped down to allow himself to be formally nominated for the role.

There are currently 1,900 National Guard members supporting border security as part of an operation named “Guardian Support,” which was launched at the start of the Trump administration.

This is in addition to some 2,300 active-duty troops assigned to border missions.

Correction: This article has been updated to reflect that welfare checks are primarily happening in Texas and Arizona.

CNN’s Geneva Sands contributed to this report.