Rumeya Öztürk, a Turkish national enrolled at Tufts University in Massachusetts, was detained by United States federal officers as she walked along a street in Boston on Tuesday.
The 30-year-old is the latest to be arrested in the Trump administration's crackdown on immigrants who have expressed their political views, particularly pro-Palestinian protesters on college campuses.
It comes amid the deportation case of Mahmoud Khalil, another student protester whose US permanent residency the White House is trying to revoke over his involvement in anti-Israel protests at Columbia University.
Here's what we know about Ms Öztürk's arrest.
What happened to Rumeysa Öztürk?
A PhD student at Tufts, Ms Öztürk was on her way to meet friends for iftar in Somerville, a meal that breaks the fast during Ramadan, on Tuesday local time when she was stopped by six plain-clothes officers, according to her lawyer, Mahsa Khanbabai.
Street CCTV footage showed all but one of the officers with their faces covered when they appeared to take away a shouting Ms Öztürk's phone and physically restrained her.
"We're the police," some of the officers is heard saying in the video obtained by the Associated Press.
A bystander is also heard asking: "Why are you hiding your faces?"
The footage shows the officers did not show their badges until after she was physically restrained.
Ms Khanbabai said the individuals who detained her client were from the US Immigration and Customs Enforcement (ICE), which falls under the Department of Homeland Security.
Why was Rumeysa Öztürk taken by ICE agents?
A senior Department of Homeland Security spokesperson said federal authorities detained Ms Öztürk after an investigation found she had "engaged in activities in support of Hamas, a foreign terrorist organisation that relishes the killing of Americans".
The department did not provide evidence to support that claim.
US Secretary of State Marco Rubio said the Trump administration had revoked at least 300 visas in an effort to clamp down on pro-Palestinian protests on university campuses.
"We do it every day," he told reporters during a stop in Guyana.
"We gave you a visa to come and study and get a degree, not to become a social activist, to tear up our university campuses."
Ms Öztürk was one of four students who wrote an op-ed in The Tufts Daily in March last year criticising the university's response to student demands that Tufts "acknowledge the Palestinian genocide", disclose its investments and divest from companies with direct or indirect ties to Israel.
Her personal details were published on pro-Israel website Canary Mission after that op-ed went online. The US government did not indicate whether Ms Öztürk's arrest pertained to that article.
Where is Rumeysa Öztürk now?
Ms Khanbabai, who said no charges had been filed against Ms Öztürk, filed a petition seeking her release on Tuesday, followed by an emergency motion on Wednesday.
In response, US District Judge Indira Talwani issued a notice stipulating the government explain by Friday why she had been detained, and ordered that officers not be able to move her outside Massachusetts without 48 hours' advance notice.
But ICE's online detainee locator system showed Ms Öztürk was being held in custody at the South Louisiana Correctional Center, about 80km north-west of Lafayette.
US government lawyers said in a court document on Thursday that she had already been transferred out of Massachusetts before the court order for her to be remanded within the state was issued.
The facility where she is being held is one of nine in Louisiana that houses immigrants waiting for legal proceedings or deportation, according to a 2024 report on ICE's website.
It marks another case of ICE agents sending immigrants taken into custody to detention centres or deporting them before a federal judge has a chance to weigh in and possibly halt their actions.
Who else has been detained in connection with universities?
Ms Öztürk's arrest appears to be part of Donald Trump's pledge to deport students he says engage in "pro-terrorist, antisemitic, anti-American activity".
She is at least the eighth individual tied to an American university known to be detained or deported by US officials since the change of government in January on accusations of spreading propaganda related to the Middle East war.
The others are Mahmoud Khalil, Yunseo Chung, Badar Khan Suri, Leqaa Kordia, Ranjani Srinivasan, Alireza Doroudi and Dr Rasha Alawieh.
Mr Khalil's case, the only one involving a Green Card holder, has been particularly noteworthy with the government seeking to cancel his permanent residency in the US using a 1952 provision of immigration law that was ruled unconstitutional in 1996.
A legal US resident and Palestinian activist, he played a prominent role in protests at Columbia University, where he was a student, last year.
He is also currently detained in Louisiana and facing deportation using a legal provision experts say has been tested just once.
Dr Alawieh, a kidney specialist from Lebanon who was due to start as an assistant professor at Brown University, was deported in March despite having a US visa because she "openly admitted" supporting a Hezbollah leader, according to Homeland Security officials.
Friends and colleagues of Ms Öztürk said she was not closely involved in pro-Palestinian protests that broke out on campuses last spring.
They said her only activism was co-authoring the Tufts op-ed.
"The only thing I know of that Rumeysa organised was a Thanksgiving pot luck," said Jennifer Hoyden, a friend who studied with Öztürk at Columbia University's Teachers College.
"There's a very important distinction between writing a letter supporting the student Senate and taking the kind of action they're accusing her of, which I've seen no evidence of."
ABC/AP
