U.S. Secretary of State Marco Rubio said on Thursday the U.S. State Department may have revoked more than 300 visas and warned that the Trump administration was looking every day for “these lunatics” after Washington this week detained and revoked the visa of a Turkish student at Tufts University.

Rubio’s comments were in response to a question about Rumeysa Ozturk, a Turkish student who was detained on Tuesday evening in Somerville, Mass., outside of Boston, by masked and plainclothes agents. Her detention was the latest Trump administration action against a foreign student who had voiced support for Palestinians in Israel’s war in Gaza.

“It might be more than 300 at this point. We do it every day. Every time I find one of these lunatics, I take away their visas,” Rubio said at a press conference in Guyana, without elaborating on whose visas had been revoked.

“At some point, I hope we run out because we’ve gotten rid of all of them, but we’re looking every day for these lunatics that are tearing things up.”

The top U.S. diplomat confirmed the State Department revoked Ozturk’s visa but did not address details when asked what specific actions Ozturk had taken that merited such a move.

Rubio said Washington would take away any visa that has been previously issued if students would participate in actions such as “vandalizing universities, harassing students, taking over buildings, creating a ruckus.”

Rubio did not say whether Ozturk had participated in those activities.

Ozturk, a Fulbright Scholar and student in Tufts’ doctoral program for Child Study and Human Development, had been in the country on an F-1 visa to study.

Rumeysa ‘spirited away’ by ICE agents, lawyer says

Her arrest came a year after Ozturk co-authored an opinion piece a year ago in the school’s student paper, the Tufts Daily, that criticized the school’s response to calls by students to divest from companies with ties to Israel and to “acknowledge the Palestinian genocide.”

Following Ozturk’s arrest, her lawyer filed a lawsuit arguing her detention was unlawful.

While a federal judge in Boston on Tuesday night ordered U.S. Immigration and Customs Enforcement (ICE) to not move Ozturk out of Massachusetts without 48 hours notice, the U.S. Department of Justice in a filing on Thursday said that she was now in Louisiana and had been detained outside of Massachusetts at the time the lawsuit was filed.

Mahsa Khanbabai, her lawyer, in a statement late on Wednesday called the claims against her client “baseless” and noted she had not been accused of any crime.

“It appears the only thing she is being targeted for is her right to free speech,” Khanbabai said.

Khanbabai said people should be “horrified at the way DHS spirited away Rumeysa in broad daylight.”

Ozturk’s supporters say her detention is the first known immigration arrest of a Boston-area student engaged in such activism to be carried out by the Trump administration, which has detained or sought to detain several foreign-born students who are legally in the U.S. and have been involved in pro-Palestinian protests.

The actions have been condemned as an assault on free speech, though the Trump administration argues that certain protests are antisemitic and can undermine U.S. foreign policy.

Columbia student flees to Canada after being caught in Trump crackdown on international students

“The people that we’re getting rid of in our country are vandalizing, they’re not protesters. They’re taking over college campuses. They’re harassing fellow students… They’re not demonstrating, they’re going beyond demonstration,” Rubio said later on Thursday at a press conference in Suriname.

“We want them out. Every one of them I find, we’re going to kick them out.”

The Massachusetts Attorney General Andrea Joy Campbell, however, called Ozturk’s detention “alarming.”

“Based on what we now know, it is alarming that the federal administration chose to ambush and detain her, apparently targeting a law-abiding individual because of her political views,” Campbell said in a statement. “This isn’t public safety, it’s intimidation that will, and should, be closely scrutinized in court.”

Wave of controversial detentions

Tufts President Sunil Kumar said in a statement the school had no advance knowledge of the arrest, which he recognized would be “distressing to some members of our community, particularly the members of our international community.”

The Turkish embassy in Washington said in a statement it was in touch with the U.S. State Department, ICE and other authorities about Ozturk’s detention.

Palestinian student activist detained by U.S. immigration agents

Ozturk was taken into custody less than three weeks after Mahmoud Khalil, a Columbia University graduate and lawful permanent resident, was similarly arrested. He is challenging his detention after Trump, without evidence, accused him of supporting Hamas, which Khalil denies.

Federal immigration officials are also seeking to detain a South Korean-born Columbia University student who is a legal permanent U.S. resident and has participated in pro-Palestinian protests, a move blocked by the courts for now.

A Lebanese doctor and assistant professor at Brown University in Rhode Island was denied re-entry to the U.S. this month and deported to Lebanon after the Trump administration alleged that her phone contained photos “sympathetic” to Hezbollah. Dr. Rasha Alawieh said she does not support the militant group but held regard for its slain leader because of her religion.

The Trump administration has also targeted students at Cornell University in New York state, Georgetown University in Washington and the University of Alabama.