The Columbia University protest ringleader busted by ICE agents and slated for deportation argued he should be released Monday, claiming the feds detained him illegally.

Anti-Israel activist Mahmoud Khalil filed a petition in Manhattan federal court claiming there was “no basis” for his arrest and detention Saturday at his university-owned apartment on the Upper West Side.

The court documents allege that Khalil’s arrest represents “the US government’s open repression of student activism and free speech, specifically targeting students at Columbia University for criticism of Israel’s assault on Gaza.”

The filing calls the former graduate student — who fronts a group called Columbia United Apartheid Divest, which has been behind numerous disruptive and at times violent campus protests at Columbia and other schools — an “outspoken activist” and claims that was the only reason for his arrest.

As four plainclothes agents from the Department of Homeland Security confronted him, Khalil showed them his immigration documents, “demonstrating that he is a lawful permanent resident — not a student visa holder,” the filing alleges.

But the Immigration and Custom Enforcement agents still grabbed him, telling him the State Department had revoked his green card and that he would be brought in front of an immigration judge, the court papers state.

It marked the first such arrest by federal authorities of an individual connected to the anti-Israel campus uprisings which began last spring.

DHS spokeswoman Tricia McLaughlin said Khalil was arrested “in support of President Trump’s executive orders prohibiting anti-Semitism.”

“Khalil led activities aligned to Hamas, a designated terrorist organization,” she said in a statement.

Khalil, a 30-year-old of Palestinian descent who grew up in Syria, was initially taken to an immigration detention facility in Elizabeth, New Jersey before being shuttled to Jena/LaSalle Detention Facility in Jena, Louisiana, according to ICE records.

A source told The Post, “They’re staging this guy for removal, but I don’t know where they’re gonna send him. We don’t have charter flights to send him to Syria.”

The filing by Khalil’s attorney names acting ICE New York field office director William Joyce, acting ICE Director Caleb Vitello, Homeland Security Secretary Kristi Noem and US Attorney General Pam Bondi as respondents, accusing them of “engaging in blatant efforts to target and chill [Khalil’s] particular viewpoints in contravention to the First Amendment and [Khalil’s] Due Process rights.”

President Trump took to Truth Social Monday afternoon to tout Khalil’s arrest — and promised more would be coming.

“Following my previously signed Executive Orders, ICE proudly apprehended and detained Mahmoud Khalil, a Radical Foreign Pro-Hamas Student on the campus of Columbia University,” he wrote, vowing it was “the first arrest of many to come” and putting universities across the country on notice.

“We know there are more students at Columbia and other Universities across the Country who have engaged in pro-terrorist, anti-Semitic, anti-American activity, and the Trump Administration will not tolerate it.”

Still, questions swirled about whether the administration will actually have legal standing to revoke green cards in instances like Khalil’s, who is married to a US citizen who is due to give birth next month, according to his lawyer.

David Vedder, a Florida-based immigration attorney, there are four grounds upon which a green card can be revoked. 

These include: living outside the US for a lengthy period without applying for a reentry permit, committing certain types of fraud, being convicted of serious offenses like drug trafficking or domestic violence and finally, violation of immigration laws, such as working without authorization or committing immigration fraud.

A White House source said Secretary of State Marco Rubio has the power to revoke green cards and was “presented with intelligence” that determined Khalil was a threat to national security

Amy Greer, Khalil’s attorney, did not respond to The Post’s request for comment Monday.

— Additional reporting by Priscilla DeGregory and Diana Glebova