New York (PTI): Ranjani Srinivasan, an Indian student at Columbia University who opted to "self-deport" after her visa was revoked, has described the terrifying moment when federal immigration agents first knocked on the door of her varsity apartment.

The immigration agents were searching for Srinivasan, 37, who had recently learned her student visa had been revoked. Srinivasan, an international PhD student from India, did not open the door when the three immigration agents knocked at it, the New York Times reported.

She was not home when the agents showed up again the next night. She packed a few belongings, left her cat behind with a friend and jumped on a flight to Canada at LaGuardia Airport, the report added.

When the agents returned a third time, this past Thursday night, and entered her apartment with a judicial warrant, she was gone.

“The atmosphere seemed so volatile and dangerous,” Srinivasan told The New York Times in an interview published on Friday, her first public remarks since leaving. “So I just made a quick decision.”

The Department of State had revoked Srinivasan's visa on March 5. The Department of Homeland Security said it obtained video footage of Srinivasan using the Customs and Border Protection (CBP) Home App to self-deport on March 11.

Her visa was revoked for allegedly "advocating for violence and terrorism" and involvement in activities supporting Palestinian militant group Hamas.

She entered the United States on a F-1 student visa as a doctoral student in Urban Planning at Columbia University, the Department of Homeland Security said in a statement on Friday. It added that Srinivasan was "involved in activities supporting" Hamas, a terrorist organisation in the US.

Srinivasan, a Fulbright recipient, was caught in the dragnet of President Trump’s crackdown on pro-Palestinian demonstrators through the use of federal immigration powers. She is one of a handful of noncitizens that the Immigration and Customs Enforcement agency has targeted in Columbia in recent days, the NYT reported.

In the week since that first knock at the door, Srinivasan says she has struggled to understand why the State Department abruptly revoked her student visa without explanation, leading Columbia to withdraw her enrollment from the university because her legal status had been terminated.

Since leaving the US last week, Srinivasan says her enrollment has been revoked without explanation from the university and that she’s not sure whether she will be able to complete the degree she has been working toward for the past five years.

“Having my visa revoked and then losing my student status has upended my life and future — not because of any wrongdoing, but because I exercised my right to free speech,” Srinivasan said in a statement to CNN.

Columbia University declined to comment on a request regarding Srinivasan’s enrollment.

Kristi Noem, the homeland security secretary, posted surveillance footage on social media that showed Srinivasan lugging a suitcase at LaGuardia as she fled to Canada, the newspaper reported.

Noem celebrated Srinivasan's departure as a “self-deportation.”

"It is a privilege to be granted a visa to live & study in the United States of America,” Noem wrote on X. “When you advocate for violence and terrorism that privilege should be revoked and you should not be in this country.”

Srinivasan’s lawyers have vehemently denied those allegations and have accused the Trump administration of revoking her visa for engaging in “protected political speech,” saying she was denied “any meaningful form of due process” to challenge the visa revocation.“

Noem’s post on X is not only factually wrong but fundamentally un-American,” Naz Ahmad, one of Srinivasan’s lawyers, said in a statement, adding: “For at least a week, DHS has made clear its intent to punish her for her speech, and they have failed in their efforts.”

In response to questions, officials with the Homeland Security Department said that when Srinivasan renewed her visa last year, she failed to disclose two court summonses related to protests on Columbia’s campus.

The department did not say how the summonses made her a terrorist sympathiser. "I’m fearful that even the most low-level political speech or just doing what we all do — like shout into the abyss that is social media — can turn into this dystopian nightmare where somebody is calling you a terrorist sympathiser and making you, literally, fear for your life and your safety,” Srinivasan said in the interview on Friday.

The Trump administration’s targeting of students with visas at a university enveloped in a cultural firestorm opened a new front in the president’s attempts to ramp up deportations and tamp down pro-Palestinian views, the NYT reported.

The president cancelled $400 million in grants to the university after accusing it of failing to protect Jewish students.