A right-wing militia group has been detaining migrants at gunpoint near the US-Mexico border then handing them over to the US Border Patrol.
According to the American Civil Liberties Union (ACLU), an armed civilian militia organization called the United Constitutional Patriots (UCP) has arrested nearly 300 people in New Mexico, including young children.
It's part of a surge in militia activity in border states as authorities struggle to deal with illegal immigration into the US.
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On Facebook the UCP describes itself as "Americans that believe in the constitution and the rights of every American that will stand up for their rights in unity and help keep America safe [sic]". Members have been posting videos to the group, showing off their captives.
One video shared shows a group of seven people being stopped at an area where a border fence ends.
"And of course as usual, this is why we're here, guys," the group's spokesman Jim Benvie says in the video. "Because there's no Border Patrol - they're busy right now."
Benvie told the NY Times his group plans on staying until President Trump's wall is built or immigration laws are changed.
"We're just here to support the Border Patrol and show the public the reality of the border," he said.
But the ACLU has written to the New Mexico governor and attorney general calling for a probe into what it calls a "fascist militia".
"The vigilante members of the organization, who posted videos and photographs of the unlawful arrests, are not police or law enforcement and they have no authority under state or federal law to detain or arrest migrants," the ACLU tweeted.
"This has no place in our country - we cannot allow armed civilians to kidnap and detain people seeking asylum."
And the US Customs and Border Protection said in a statement it "does not endorse or condone private groups or organizations that take enforcement matters into their own hands" and those responsible could face "legal consequences".
But the UCP warns it will continue to arrest and detain migrants attempting to cross the border.
"We will continue to fight the good fight, we will continue to stand in the gap. We will complete our mission," one of the group's leaders said on Facebook.
"Please know that despite what our detractors are saying, nothing we are doing is illegal or improper."