A group of more than 300 migrants trying to cross into the U.S. from Mexico surrendered to an armed militia group in New Mexico earlier this week, according to videos posted on social media.

The United Constitutional Patriots detained the Central American asylum seekers at gunpoint Monday night before turning them over to U.S. Customs and Border Protection agents.

The militia group, made up of former police officers and military veterans, has stood guard along the southern border in Sunland Park, New Mexico, for the past two months. Jim Benvie, a spokesman for the group, told the New York Times that they plan to stay put monitoring the border until a wall is built or until lawmakers tighten immigration laws.

"We're just here to support the Border Patrol and show the public the reality of the border," Benvie told the newspaper.

Sunland Park sits along the southern border near the Mexican city of Ciudad Juarez, just west of El Paso, Texas.

A surge in immigrants trying to cross into the U.S. has pushed CBP, along with other government agencies, to its "breaking point." Agencies don't have the resources to handle the overwhelming number of Central Americans coming into the U.S.

"CBP is facing an unprecedented humanitarian and border security crisis all along our Southwest border and nowhere has that crisis manifested more acutely than here in El Paso," then-Customs and Border Protection Commissioner Kevin McAleenan told reporters last month. Earlier this month, McAleenan was named acting-secretary of the Department of Homeland Security following the resignation of Secretary Kirstjen Nielsen.

What's the story?

Benvie said the members have experience in law enforcement or the military and are simply trying to assist border officials.

"We're just Americans. We're veterans, we're ex-law enforcement, we're people that care about our national security," Benvie told the Daily Mail. "We're people that care about our strained Border Patrol."

The 43-year-old compared the group's actions to a "verbal citizen's arrest."

Benvie, along with three other men, were patrolling Monday night when they spotted hundreds of migrants coming toward them.

"We held them there until Border Patrol came," he explained to the Daily Mail. "And once they came then we did what we do, and that's to help Border Patrol get them to the processing van. So, everybody is safe."

He described the group's actions as a "citizen's arrest" and claimed that Border Patrol officials have not asked the group to stop detaining border crossers.

"If these people follow our verbal commands, we hold them until Border Patrol comes," Benvie told the NY Times. "Border Patrol has never asked us to stand down."

What did Border Patrol say?

Customs and Border Protection spokesman Carlos A. Diaz declined Fox News' request for comment about the United Constitutional Patriots or the recent incident.

However, he said the federal agency "does not endorse private groups or organizations taking enforcement matters into their own hands."

What did the governor of New Mexico say?

The state's governor told the NY Times that she considered the group's actions "completely unacceptable," adding that migrant families shouldn't be "menaced or threatened in any way, shape or form" when they cross the border.

What else?

Benvie said CBP officers instructed the group to refrain from pointing their firearms at the migrants, adding that it has issued a new rule prohibiting members from patrolling with military-style weapons, according to the NY Times.

The members are still allowed to carry handguns on patrol.

Watch:

Watch the video of the detained migrants that was posted on Facebook Monday night.

This story has been updated. The original version incorrectly stated that Sunland sits to the east of El Paso. It has been corrected.