U.S. immigration agents arrested a Palestinian graduate student who has played a prominent role in pro-Palestinian protests at New York's Columbia University as part of U.S. President Donald Trump's promised crackdown on some anti-Israel activists.

Mahmoud Khalil, a student at the university's School of International and Public Affairs, was arrested by U.S. Department of Homeland Security agents at his university residence on Saturday evening, the Student Workers of Columbia labor union said in a statement.

His wife is a U.S. citizen, eight months pregnant, according to news reports, and he holds a U.S. permanent residency green card, the union said. His arrest was condemned by civil rights groups as an attack on protected political speech.

In an interview with Reuters hours before his arrest on Saturday about Trump's criticism of student protesters, Khalil said he was concerned that he was being targeted by the government for speaking to the media.

Secretary of State Marco Rubio shared a news report of Khalil's arrest on social media on Sunday, adding the comment: "We will be revoking the visas and/or green cards of Hamas supporters in America so they can be deported." He did not elaborate and spokespeople for Rubio did not respond to questions.

The Department of Homeland Security said in a social media post that it had arrested Khalil because he has "led activities aligned to Hamas," without elaborating. DHS spokespeople did not respond to Reuters questions.

U.S. law forbids, opens new tab providing "material support or resources" to groups the U.S. has designated as terrorist organizations, including Hamas, the Palestinian-nationalist Islamist group that governs Gaza and controls the territory's militant wing. That law does not define or prohibit "activities aligned to" these groups, and DHS spokespeople did not respond to questions about their accusation.

Neither department has said Khalil is accused of giving material support to Hamas, or of any other crime.

Khalil's detention is one of the first efforts by Trump, a Republican who returned to the White House in January, to fulfill his promise to seek the deportation of some foreign students involved in the pro-Palestinian protest movement, which he has called antisemitic. The Hamas attack on Israel in October 2023 and subsequent U.S.-supported Israeli assault on Gaza have led to months of pro-Palestinian and anti-Israel protests that have roiled college campuses in the U.S. and overseas.

Khalil calls it an anti-war movement that includes Jewish students and groups, who reject antisemitism allegations. He was one of the lead negotiators with school administrators for the pro-Palestinian student protesters, some of whom set up tent encampments on Columbia lawns last year and seized control of an academic building for several hours before Columbia called in police to arrest them.

He was not among the several dozen students that occupied the building, but was a mediator between Columbia vice provosts and the protesters.

Some Israeli and Jewish students have said the protests have been threatening and disruptive and have organized pro-Israel counter-protests.

The New York Civil Liberties Union said Khalil's detention was unlawful, retaliatory and an attack on free speech rights.

Donna Lieberman, the group's executive director, said in a statement the detention "is a frightening escalation of Trump’s crackdown on pro-Palestine speech, and an aggressive abuse of immigration law."

Khalil grew up in a Palestinian refugee camp in his native Syria and has worked for the British embassy in Beirut, according to an online biography, opens new tab. He was being held on Sunday at a U.S. Immigration and Customs Enforcement detention center in Elizabeth, New Jersey, according to the ICE online detainee locator. Khalil's wife declined to comment through one of Khalil's fellow students.

A spokesperson for Columbia said the school was barred by law from sharing information about individual students, but said in a statement the school was "committed to the legal rights of our students."

Spokespeople for Trump did not respond to questions.

TRUMP CANCELS CONTRACTS

Trump has singled out Columbia for its handling of student protesters and has quickly increased pressure on the school: Khalil's arrest came a day after the Trump administration said it had canceled government contracts and grants awarded to Columbia University worth about $400 million. It said the cuts and the student deportation efforts, which face legal challenges, are because of antisemitic harassment "on and near" Columbia's Manhattan campus.

"What more can Columbia do to appease Congress or the government now?" Khalil told Reuters hours before his arrest, noting that Columbia had repeatedly called in police to arrest protesters and had disciplined many pro-Palestinian students and staff, suspending some. "They basically silenced anyone supporting Palestine on campus and this was not enough. Clearly Trump is using the protesters as a scapegoat for his wider agenda fighting and attacking higher education and the Ivy League education system."

Columbia's interim president, Katrina Armstrong, said the school was committed to combating antisemitism and other prejudice and was "working with the federal government to address their legitimate concerns."

Khalil and other protesters have demanded for several years that Columbia end investments of its $14.8 billion endowment in weapons manufacturers and companies that support Israel's government and military. Columbia said it was willing to expedite consideration of the students' demands through its advisory committee, opens new tab on socially responsible investing.

FRIEND 'HORRIFIED' BY ARREST

Maryam Alwan, a Palestinian American senior at Columbia who has protested alongside Khalil, said Trump was dehumanizing Palestinians.

"I am horrified for my dear friend Mahmoud, who is a legal resident, and I am horrified that this is only the beginning," she said.

Columbia issued a revised protocol this week for how students and school staff should deal with federal immigration agents seeking to enter private school property, saying they could enter without a judicial arrest warrant in "exigent circumstances," which it did not specify.

"By allowing ICE on campus, Columbia is surrendering to the Trump administration's assault on universities across the country and sacrificing international students to protect its finances," the Student Workers of Columbia said in its statement.