An Irish American immigration activist prevented two undocumented immigrants from being arrested by ICE by explaining his constitutional rights.

On March 5, Bryan MacCormack, the executive director of the Columbia County Sanctuary Movement (CCSM), an immigrant advocacy group in upstate New York, was pulled over by ICE while driving two undocumented immigrants from Hudson City Court to help them deal with minor traffic citations, the Daily Mail reports.

According to MacCormack, his car was pulled over by Immigration and Customs Enforcement deportation agents who produced a “warrant of arrest of alien.”

The document, which is authorized by the Department of Homeland Security, directs federal immigration enforcement agents to arrest the person named not he warrant, it does not authorize agents to demand entry not a home or private space to make the arrest, as MacCormack explained.

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In a video recorded by a backseat passenger in the vehicle, MacCormack can be heard explaining to the officer that the papers he’s holding are not a warrant for arrest.

“Yes they are, sir, warrant of arrest of alien,” answers the officer.

“Yeah, warrant of arrest of alien, not signed by a judge. It's not a judicial warrant. I have no obligation to oblige by that warrant,” MacCormack tells him.

The agent then tells the driver: “This is a lawful warrant under the authority of the Immigration and Nationality Act.”

“Signed by a judge?” MacCormack asks.

“You have no jurisdiction over me as a citizen,” he adds. “I’m the driver of this vehicle.”

ICE then called for backup from the Hudson Police Department, which dispatched two cars to the scene.

MacCormack called his attorney, who also came to the scene and told the officers they could not hold his client without a judicial warrant. MacCormack and his passengers were then able to continue on their way.

MacCormack brought the two undocumented immigrants, who had remained silent throughout the encounter, to a local interfaith church, where they were able to enter into sanctuary.

CCSM shared the video earlier this month with a news release explaining the encounter. The video has since gone viral.

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After the incident, an ICE spokesperson issued a statement saying the officers were seeking two people not lawfully present int he country and that MacCormack, “interfered with the enforcement action, causing officers to instead depart the scene to avoid further disruption.”

“Individuals who intervene in or seek to impede ICE officers while they are carrying out their mission recklessly endanger not only the enforcement personnel but also the individuals targeted for arrest and potentially innocent bystanders,’” the statement said.

“Those who engage in such actions expose themselves to potential criminal violations and run the risk of harming the very people they purport to support.”

In an interview with NBC News, MacCormack said: “I was nervous and felt fear for the safety of myself and the community members inside of my vehicle. But I was also inherently indignant at ICE's tactics and their relentless pursuit and practice of detention, deportation and family separation.”