The Trump administration has set off a legal and ethical firestorm by targeting international students at U.S. colleges for deportation, including some whom the government alleges participated in pro-Palestinian protests or activities on campuses.

The Trump administration has claimed without presenting evidence that some of those students support the terrorist organization Hamas, while the students say the White House is treading on their constitutional right to free speech and the longstanding tradition of participating in campus demonstrations.

Since President Trump’s Jan. 30 executive order to “combat the explosion of anti-Semitism on our campuses and streets” in the aftermath of the Oct. 7, 2023, Hamas attack on Israel, the State Department has revoked around 300 visas so far, many of them held by college students alleged to have participated in pro-Palestinian activities on the nation’s campuses, according to Secretary of State Marco Rubio.

“If you apply for a visa to enter the United States and be a student, and you tell us the reason you are coming to the United States is not just because you want to write op-eds, but because you want to participate in movements that are involved in doing things like vandalizing universities, harassing students, taking over buildings, creating a ruckus – we’re not going to give you a visa,” Rubio said, adding, “Every time I find one of these lunatics, I take away their visa.”

Here’s what we know and don’t know about some of the more high-profile cases involving foreign students who have had their visas revoked, who have been detained, or who have self-deported after being targeted by federal Immigration and Customs Enforcement (ICE) agents.

Mahmoud Khalil

Mahmoud Khalil, a 30-year-old Columbia University international affairs graduate student of Palestinian descent, was arrested on March 8 when ICE agents appeared at his student apartment building, despite him being a legal permanent U.S. resident in possession of a green card. Khalil is married to an American citizen, who is pregnant with their first child.

The Trump administration accused Khalil, a Palestinian activist, of supporting Hamas and distributing “pro-Hamas propaganda,” though it has provided no evidence to support that claim. White House press secretary Karoline Leavitt claimed on March 11 that Khalil distributed “pro-Hamas propaganda fliers with the logo of Hamas,” but declined to provide details.

Ramzi Kassem, the director of CLEAR, a group representing Khalil, called Leavitt’s claim “nonsense” and said there is “no truth to it whatsoever.”

During a pro-Palestinian student protest at Columbia University last spring, Khalil served as a negotiator when students bargained with school officials over a tent encampment they established on campus. During the days-long demonstration, some protestors also occupied the school’s Hamilton Hall and defied orders to disperse, prompting the university to write a letter formally allowing the New York Police Department to enter the campus and break up the protest, during which time they made dozens of arrests. Khalil was not among those arrested, according to the NYPD, who confirmed to ABC News that “there are no arrests on file” for Khalil.

“His one and only goal was to get Columbia University to divest from its complicity with Israeli government crimes in Gaza and the West Bank,” Kassem said of Khalil’s involvement in the protests.

Khalil is being held at an ICE detention facility in Louisiana and has filed a lawsuit challenging the federal government’s attempt to deport him. He has not been charged with a crime, although the government alleges he intentionally misrepresented information on his green card application and therefore is inadmissible to the United States.

According to recent court filings, the Trump administration said Khalil failed to disclose when applying for his green card last year that his employment by the Syria Office at the British Embassy in Beirut went “beyond 2022” and that he was a “political affairs officer” for the United Nations Relief and Works Agency for Palestine Refugees (UNWRA) from June to November 2023.

In arresting Khalil, the government invoked a rarely used provision of immigration law that they said allows the secretary of state to revoke the legal status of people whose presence in the country could have “adverse foreign policy consequences.”

In a letter he released from the detention facility in which he’s being held, Khalil described himself as a “political prisoner.”

“My arrest was a direct consequence of exercising my right to free speech as I advocated for a free Palestine and an end to the genocide in Gaza, which resumed in full force Monday night,” Khalil wrote in the March 18 letter, referring to the renewed attacks on Gaza after the collapse of the ceasefire.

A federal judge in New Jersey on April 2 retained Khalil’s case, rejecting the government’s request to move it to Louisiana or dismiss it altogether. The opinion, unless appealed by the government, would clear the way for the judge to decide the more substantive issues of Khalil’s continued confinement.

Khalil is scheduled to appear before an immigration judge for a removal hearing on April 8.

Ranjani Srinivasan

An urban planning doctoral student at Columbia University, Ranjani Srinivasan, a citizen of India who was in the country on an F-1 student visa, used the U.S. Customs and Border Protection home app to self-deport on March 11, according to Department of Homeland Security (DHS) Secretary Kristi Noem.

“Srinivasan was involved in activities supporting Hamas, a terrorist organization,” Noem said in a March 14 statement, which did not include evidence to support the allegation against Srinivasan.

“I am not a terrorist sympathizer so I just kind of find it absurd,” Srinivasan said during a CBC interview March 19. “I’m a Ph.D. student … who actually rarely left the office because I was busy working or grading my students’ papers.”

In a March 22 statement, the group Student Workers of Columbia – of which Srinivasan is a member, the union confirmed in response to an ABC News request for comment – said Srinivasan was notified on March 6 that her student visa had been revoked and that on March 8, ICE agents went to her Columbia housing apartment seeking entry, allegedly without a warrant, but did not arrest or detain anyone. Srinivasan was subsequently informed by the university’s International Students and Scholars Office that she was being disenrolled by the university and ordered to vacate her student housing, according to the Student Workers of Columbia statement.

“With no housing or visa and a continued stream of threats from ICE to detain her, Ranjani made the difficult decision to leave the country for Canada,” according to the statement.

Srinivasan has not been charged with a crime. The Student Workers of Columbia has been circulating a petition asking Columbia to re-enroll Srinivasan and for the government to reinstate her visa.

Leqaa Kordia

A Palestinian from the West Bank, Leqaa Kordia was arrested on March 13 by the Department of Homeland Security.

According to DHS, Kordia was arrested for allegedly overstaying her expired visa, which the agency said terminated on Jan. 26, 2022.

In a March 14 statement, DHS said that Kordia’s student visa was terminated for lack of class attendance. She was previously arrested in April 2024 for her alleged involvement in pro-Palestinian protests at Columbia, according to the DHS statement.

“Columbia has no record of this individual being registered as a current or former student at the University,” a spokesperson for the university said in response to an ABC News request for comment.

“It is a privilege to be granted a visa to live and study in the United States of America. When you advocate for violence and terrorism that privilege should be revoked, and you should not be in this country,” DHS Secretary Noem said in a statement following Kordia’s arrest.

Multiple attempts to determine the current status of Kordia’s case and whether she is currently being detained, including repeated ABC News inquiries to ICE and DHS, were not immediately successful.

Yunseo Chung

Yunseo Chung, a junior at Columbia University, filed a lawsuit against the Trump administration after ICE agents went to her residence on March 13 looking for her, one day after an ICE official signed an administrative arrest warrant for her, according to her lawsuit.

According to her lawsuit, Chung was born in South Korea but is a lawful permanent U.S. resident who has lived in the United States since she was 7 years old.

“This action challenges the government’s shocking overreach in seeking to deport a college student, Plaintiff-Petitioner Yunseo Chung, who is a lawful permanent resident of this country, because of her protected free speech,” according to Chung’s lawsuit, filed in U.S. District Court for the Southern District of New York. “The government’s actions are an unprecedented and unjustifiable assault on First Amendment and other rights, one that cannot stand basic legal scrutiny.”

The lawsuit contends, “Simply put, immigration enforcement – here, immigration detention and threatened deportation – may not be used as a tool to punish noncitizen speakers who express political views disfavored by the current administration.”

According to her lawsuit, Chung has participated since 2023 in student protests on the Columbia campus related to Israel’s military campaign in the Gaza Strip. On March 5, Chung was among a group of students arrested by the New York Police Department for holding a sit-in at an academic building at Barnard College, according to her lawsuit. She was given a desk appearance ticket accusing her of obstruction of governmental administration, her lawsuit claims.

The Department of Homeland Security said in a March 25 statement that Chung had engaged in “concerning conduct” and cited her prior arrest during a protest at Barnard College, which DHS described as a “pro-Hamas” protest.

“ICE HSI will investigate individuals engaged in activities in support of Hamas, a foreign terrorist organization,” the DHS statement said.

“Ms. Chung has felt moved to join efforts to advocate for Palestinian human rights,” the lawsuit states, under a heading titled Ms. Chung’s Exercise of Free Speech Rights in Support of Palestinians.

“Ms. Chung has also felt compelled to criticize Columbia for its handling of student protests supporting Palestinian human rights, including the punitive measures imposed on certain students,” according to the lawsuit.

Chung’s lawsuit also states that some opponents of pro-Palestinian protest activities “frequently mischaracterize” them as “inherently supportive of Hamas or terrorism and anti-Semitic.”

A federal judge in New York issued a temporary restraining order on March 25 blocking federal agents from detaining Chung.

Rumeysa Ozturk

A Ph.D. student at Tufts University in Massachusetts, Rumeysa Ozturk, a Turkish national with a valid F-1 visa, was arrested by ICE agents on March 25 near her home in the Boston suburb of Somerville, Massachusetts.

In a statement to ABC News, a DHS spokesperson said: “Rumeysa Ozturk is a Turkish national and Tufts University graduate student, granted the privilege to be in this country on a visa. DHS and ICE investigations found Ozturk engaged in activities in support of Hamas, a foreign terrorist organization that relishes the killing of Americans.” The DHS statement did not specify the activities in which Ozturk is alleged to have participated.

“A visa is a privilege not a right. Glorifying and supporting terrorists who kill Americans is grounds for visa issuance to be terminated,” the DHS statement further said.

On March 26, 2024, Ozturk, a Fulbright scholar, was one of four Tufts students who wrote an op-ed published in the school student newspaper, The Tufts Daily, asking the university to agree to resolutions passed by the Tufts Community Senate to divest from companies with direct or indirect ties to Israel.

“Credible accusations against Israel include accounts of deliberate starvation and indiscriminate slaughter of Palestinian civilians and plausible genocide,” the op-ed said, in part. It’s unknown whether the editorial played a part in Ozturk’s arrest.

“Rumeysa has not been accused of committing any crime. It appears the only thing she is being targeted for is her right to free speech,” Mahsa Khanbabai, an attorney representing Ozturk, said in a statement provided to ABC News.

A statement in support of Ozturk, dated April 1 and signed by Tufts President Sunil Kumar, acknowledges the March 26 editorial, and further states that the university “has no information to support the allegations that [Ozturk] was engaged in activities at Tufts that warrant her arrest and detention,” and that it “has no further information suggesting that she has acted in a manner that would constitute a violation of the University’s understanding of the Immigration and Naturalization Act.”

Ozturk is currently listed in the ICE database as “in custody” and appears to be held at an ICE processing center in Basile, Louisiana.

On March 25, a federal judge in Boston ruled that Ozturk cannot be deported until the judge determines whether the court has jurisdiction to decide whether Ozturk was lawfully taken into custody.

Judge Denise Casper said in her ruling that Ozturk “shall not be removed from the United States until further Order by this Court.”

Following an April 3 hearing, Judge Casper did not issue a ruling and said she will first decide whether she has jurisdiction before other motions in the lawsuit can be considered.

Alireza Doroudi

Alireza Doroudi, an Iranian citizen and a doctoral student studying mechanical engineering at the University of Alabama, was arrested at his home on March 25.

The Department of Homeland Security said Doroudi’s student visa was revoked and he was subsequently arrested because he “posed significant national security concerns.”

But Doroudi’s attorney, David Rozas, told ABC News that he has “not been informed of any allegations concerning significant national security issues.”

Rozas said Doroudi has “not been arrested for any crime, nor has he participated in any anti-government protests.”

Doroudi was initially held in a county jail in Alabama but has since been transferred to ICE’s Jena-LaSalle Detention Facility in Louisiana, according to the ICE website.

“He is legally present in the U.S., pursuing his American dream by working towards his doctorate in mechanical engineering,” Rozas said. “He is also in the early stages of applying for an EB-1/Adjustment of Status as a researcher with extraordinary ability.”

Rozas said Doroudi is studying at the University of Alabama on active I-20/SEVIS status, referring to the Student and Exchange Visitor Program.

Momodou Taal

A Ph.D. student of Africana studies at Cornell University, Momodou Taal filed a federal lawsuit on March 15 seeking to block the enforcement of Trump executive orders that he feared could lead to his deportation.

But six days after filing the lawsuit, the 31-year-old citizen of the U.K. and Gambia was asked to voluntarily surrender to ICE agents, according to his attorneys.

In its court filing, the Department of Justice said Taal’s student visa was revoked before he filed his lawsuit but ICE agents had trouble locating him. The revocation is based on Taal’s alleged involvement in “disruptive protests,” disregarding university policies and creating a hostile environment for Jewish students, the government said.

According to court records, Taal was temporarily suspended from Cornell for a second time last fall after a group of pro-Palestinian activists disrupted a campus career fair. He has limited access to the upstate New York campus as he continues his studies remotely, according to his attorneys.

“If the First Amendment does not protect the right to attend a demonstration, what’s left? Not much,” said Taal’s attorney, Eric Lee.

On March 27, a federal judge denied Taal’s bid to prevent his deportation and his challenge of two Trump executive orders that have been used to target other pro-Palestinian students.

Taal announced on Monday that he has exited the United States and is “safe” in an undisclosed country.

“Today I took the decision to leave the United States, free and with my head held high,” Taal said in a social media post.

While his lawyers planned to make another legal argument for a temporary restraining order, Taal wrote in his post: “Given what we have seen across the United States, I have lost faith that a favorable ruling from the courts would guarantee my personal safety and ability to express my beliefs.”

“I have lost faith I could walk the streets without being abducted. Weighing up these options, I took the decision to leave on my own terms,” Taal’s post continued. “This is of course not the outcome I had wanted going into this, but we are facing a government that has no respect for the judiciary or for the rule of law.”

Badar Khan Suri

A visiting scholar from India and a researcher at Georgetown University, Badar Khan Suri was detained on March 17 outside his Washington, D.C.- area apartment.

The Department of Homeland Security alleged that Suri was “actively spreading Hamas propaganda and promoting antisemitism on social media.” The department also alleged he had close connections to a “known or suspected terrorist” who is a senior adviser to Hamas.

Suri, who is married to Mapheze Saleh, a U.S. citizen of Palestinian descent, was sent to an ICE detention facility in Louisiana, according to his attorney.

A lawsuit filed by Suri’s attorneys said the Trump administration appeared to be targeting the Georgetown University fellow due to his wife’s identity as a Palestinian and her constitutionally protected speech.

“This was done pursuant to a policy to retaliate against and punish noncitizens like Mr. Suri solely for their family ties to those who may have either expressed criticism of U.S. foreign policy as it relates to Israel,” attorneys representing Suri said in a complaint.

In a sworn declaration filed March 20 in U.S. District Court for the Eastern District of Virginia, Mapheze Saleh said that following the Oct. 2023 attack by Hamas on Israel, she “shared posts on a daily basis” about subsequent events in Gaza, “including posts that expressed sorrow for the deaths of Gazan people.” Because of this, Saleh said, and because her father previously served in the government of Gaza until 2010, “multiple articles were published about me and my family, and eventually about my husband. A website claimed falsely that my husband and I have ‘ties to Hamas.'”

Nermeen Arastu, one of Suri’s attorneys, told ABC News that Suri’s detainment happened because “President Trump wants to silence anyone he suspects to hold a political opinion contrary to his.”

Suri has not been accused of a crime, his lawyers said.

Georgetown University said Suri was granted a visa to enter the United States to continue his doctoral research on peacebuilding in Iraq and Afghanistan.

ABC News’ Ely Brown, Lucien Bruggeman, Nadine El-Bawab, Armando Garcia, James Hill and Laura Romero contributed to this report.