The University of Minnesota graduate student who was detained by immigration agents last week had not participated in campus activism or been outspoken about political issues, according to a lawsuit he filed on Sunday in federal court challenging the legality of his arrest.

Instead, the issue that appears to have put the student, Dogukan Gunaydin, on the radar of Immigration and Customs Enforcement is more mundane: a 2023 drunken-driving case in which he pleaded guilty.

After the university disclosed in a statement Friday night that a student had been taken into immigration custody, there was rampant speculation that the incident was related to pro-Palestinian activism, as has been the case at several other universities. Top elected officials, including Gov. Tim Walz of Minnesota and members of Congress, issued statements expressing concern, and students held protests on campus.

But no evidence of activism emerged in the case of Mr. Gunaydin, 28, a Turkish citizen who was pursuing a master’s degree in business administration. In an emailed statement, the Homeland Security Department said that Mr. Gunaydin had been arrested after the State Department revoked his visa over the D.U.I. case. “This is not related to student protests,” the statement said.

Immigration lawyers and other experts say they worry that the detention may signal a new front in the Trump administration’s approach to immigration enforcement.

The government routinely revokes student visas over criminal cases, but typically the holder has the opportunity to challenge the revocation with the help of a lawyer, or is allowed to leave the country voluntarily.

Mr. Gunaydin’s case was different. Another puzzling fact, according to the lawsuit, was that a computer system did not show his visa as revoked until several hours after he was taken into custody Thursday morning.

Starting in 2015, the State Department issued guidance making clear that a drunken-driving arrest could be grounds to revoke a visa. Since then, according to Debra Schneider, an immigration lawyer in Minneapolis, many foreigners working or studying in the United States have received letters notifying them about the revocation of a visa after a run-in with the law.

Yet, Ms. Schneider said, people on temporary work and student visas often manage to get visas reinstated, particularly if the circumstances of their cases are not egregious.

“I have never had someone put in custody by ICE over a D.U.I.,” she said.

In an emailed statement, the State Department said it would not discuss Mr. Gunaydin’s case, citing privacy considerations. But the department said: “The United States has zero tolerance for noncitizens who violate U.S. laws. Those who break the law, including students, may face visa refusal, visa revocation and/or deportation.”

Hannah Brown, Mr. Gunaydin’s lawyer, did not respond to requests for comment on Monday.

Mr. Gunaydin was taken into custody at approximately 9:30 a.m. Thursday after he stepped out of his St. Paul, Minn., residence to head to class, according to the lawsuit. The immigration agents drove him to the ICE office in St. Paul, where officials told the student that his visa had been “retroactively revoked,” according to the lawsuit.

“Mr. Gunaydin feared he was being kidnapped,” the lawsuit said, adding that officials provided no information on why the visa had been revoked.

That afternoon, roughly seven hours after Mr. Gunaydin was taken into custody, the online government registry of international student visa information showed that his visa had been revoked, according to the lawsuit. The system did not provide a clear explanation for the revocation but listed him as having failed to maintain legal status.

That evening, Mr. Gunaydin was told that he would be seeing an immigration judge on April 8, and he was later booked into the Sherburne County jail, which is roughly 35 miles northwest of downtown Minneapolis.

It was not clear on Monday whether Mr. Gunaydin had been formally placed in deportation proceedings.

His lawsuit lists President Trump, Secretary of State Marco Rubio and several senior officials at Homeland Security as defendants. The suit also seeks Mr. Gunaydin’s release from custody, arguing that his arrest violated his constitutional right to due process, as well as administrative law, because his visa was still valid when immigration agents took him into custody.

Carl C. Risch, who oversaw visa matters for most of Mr. Trump’s first term as an assistant secretary of state, said officials revoked visas as a result of arrests with “great frequency” over the years. But he suggested that it was unusual for agents to detain an international student over an old D.U.I. case without warning.

Mr. Risch, who is now in private practice at Kurzban Kurzban Tetzeli & Pratt, said federal authorities would historically have sought to detain “someone who was considered to be a danger to the community, perhaps somebody with a very serious or concerning criminal background, ties to terrorist organizations.”

If the government starts regularly detaining and deporting visa holders over misdemeanors like drunken-driving, Mr. Risch said, that would constitute a “change in policy, an escalation.”

On Monday, the president of another Minnesota school — Minnesota State University, Mankato — revealed that a student there was also taken into ICE custody last week.

The president, Edward S. Inch, said that no reason was given for the arrest on Friday. He said in a statement that he had reached out to state and federal officials “to share my concern and ask for their help in curbing this activity within our campus community of learners.”

The statement neither identified the student nor provided details of the events leading up to the arrest.

Mr. Gunaydin was arrested on June 24, 2023, after a Minneapolis police officer described seeing a car maneuver erratically around 1:50 a.m., according to a charging document. Mr. Gunaydin told the officer that he had drunk vodka earlier that evening, according to the document. A breathalyzer test showed that he had an alcohol blood level of 0.17 percent — well over the 0.08 percent legal limit to drive.

In March of last year, Mr. Gunaydin pleaded guilty to driving while impaired, a misdemeanor, according to court records. A judge ordered him to perform community service, attend a D.U.I. clinic and refrain from future traffic violations.

After the conviction, the lawsuit said, Mr. Gunaydin was admitted into business school and awarded a scholarship.

“He has maintained a full course load with a high G.P.A. and served in the M.B.A. Student Association,” according to the lawsuit.

Ana Ley and Stephanie Saul contributed reporting.

No matter how you slice it, Liz Moore has arrived.

This month, an adaptation of her blockbuster novel “Long Bright River” started streaming on Peacock. And her next book, “The God of the Woods,” now on the best-seller list for 36 weeks (and counting), will soon hit the million mark in sales — a distinction normally reserved for celebrities and novelists recognizable by last name alone.

Moore isn’t one of those authors. But, over the past two decades, she’s proved to be “a writer who can do anything,” as her editor Sarah McGrath put it.

Moore taps into an elusive sweet spot between literary and commercial fiction, populating vividly drawn settings with characters who seem to live, breathe and make terrible mistakes along with the rest of us. Her novels can be enjoyed by, say, a teenage girl and her 50-something father, defying genre and categorization to such an extent that, from one to the next, a reader might not register that they’re written by the same person.

“I get messages saying, I loved your new book. Do you have any others?” Moore, 41, said during an interview at a cafe in Philadelphia. “Or they’ll call ‘The God of the Woods’ my second book because ‘Long Bright River’ was my first that broke out.”

In fact, “The God of the Woods,” a mystery about siblings who disappear 14 years apart, is Moore’s fifth book. She wrote her first, “The Words of Every Song,” while she was a student at Barnard College. Shortly after she graduated in 2005, she signed on with an agent who’d come to campus for a panel on the publishing industry.

“I reached out and said, ‘I have this manuscript of interconnected stories about the music industry. Would you be interested in looking at it?’ She said yes,” Moore recalled. “Only in retrospect do I realize what a lucky break that was.”

At the time, Moore was more focused on singing than she was on fiction: Her folk album, “Backyards,” came out in 2007, the same year as “The Words of Every Song.” But it was her prose that attracted attention: The rock critic Robert Christgau described Moore’s book in The New York Observer as “likable, well-rendered, sweet.” He also praised her “wholesome values.”

In her early 20s, Moore worked in the editorial department of the Morgan Library and at Matt Umanov Guitars in the West Village. Gradually, she said, “I gave myself permission to think, Maybe fiction is something I could pursue in a more serious way.”

She got an M.F.A. at Hunter College, where she studied with Nathan Englander and Colum McCann and started working on her second novel, “Heft.” Her first agent had left the industry, and a second one, with whom she worked for more than a year, ultimately declined to represent the project.

After a dozen or so rejections, she signed on with Seth Fishman at the Gernert Company, who sold “Heft” and a third novel, “The Unseen World,” to W.W. Norton & Company. Both are tender and brainy — the literary equivalent of folk songs, with characters who hold the note.

“‘Heft’ did better than expected and ‘The Unseen World’ did more poorly than expected,” Moore said. The latter, which a Times reviewer called “fiercely intelligent,” came out in July 2016, two months after Moore’s daughter was born.

“I didn’t know how hard it would be when I agreed to go on tour with a newborn,” Moore said. “I was pumping in the bathroom. I was sleep deprived. I thought it would be possible and it was just …” She didn’t finish the sentence.

During that time Moore wasn’t sure she’d be able to complete another book, let alone sell it. But she kept writing and teaching — first at Holy Family University in Philadelphia, then at Temple University, where she now directs the graduate-level writing program.

“I was raised never to quit a day job,” Moore said. “I also love the community of teaching.”

“Long Bright River” grew out of a photo essay Moore worked on in 2009, when she first moved to Philadelphia. Jeffrey Stockbridge, a photographer, took pictures of women in the Kensington neighborhood who were struggling with addiction, and Moore wrote their stories. After the piece was published in “The Rust Belt Rising Almanac” (2013), she kept going back to Kensington, leading free writing workshops at a women’s day shelter for two years.

A story started to take shape, about a detective searching for her sister, who’s addicted to drugs.

“Since birth, I’ve been surrounded by family members in various states of active use or recovery,” Moore said. “I never name who they are, I don’t wish to speak for them or tell their stories, but my own story is being well versed in the language of addiction.”

Moore worked on “Long Bright River” for about four years, her average germination period. In 2018, Gernert sold the book to McGrath at Riverhead in a heated auction.

“I’m always looking for literary fiction that can reach a wide audience,” McGrath said. “I didn’t know I was looking for a police detective in Philadelphia. But Liz writes rich characters with such compassion, and she creates a real sense of place.”

The book, which came out on Jan. 7, 2020, was an instant best seller, a ”Good Morning America” Book Club pick and one of Barack Obama’s favorite books of 2020.

“It forced open certain conversations that had been buried in my family,” Moore said. “That was cathartic for everybody.”

About two months later, when the Covid pandemic struck, she was teaching a full course load via Zoom while caring for her daughter, who was 3, and her son, then 10 months old.

Moore said, “My husband and I built an improvised playpen in the living room.” They took turns working on the upper floor of their South Philadelphia rowhouse. Eventually Moore started waking up at 5 o’clock in the morning so she could squeeze in a few hours of writing.

“‘The God of the Woods” started “as an act of desperation, of trying to find out who I was again,” she said. “I went into autopilot and thought, I just have to do this.”

The book was “hellish” to write, Moore admitted: “It has so many characters. It has so many timelines. I never outline, so I just write and experiment and fail.”

Her approach brings a sense of immediacy to the mysteries surrounding the missing Van Laar children, who are practically royalty in the small Adirondack town where their wealthy family summers as a verb. One has the sense of the two cases being cracked in real time, even though the bulk of the action takes place in 1975.

The setting held particular meaning for Moore: Her ancestors settled in the Adirondacks, her grandmother was born nearby and her family still has a cabin in the southern part of the region. “It’s a special, almost spiritual place for us,” Moore said.

“The God of the Woods” was a Book of the Month Club pick and was voted in as the “Tonight Show” summer read for 2024. The book gained momentum from there, becoming such a stalwart on the best-seller list that the Riverhead team no longer calls Moore to announce the news. She receives a weekly email instead, and she doesn’t take it for granted.

Moore seemed pleased, if cautiously so, about the fandom she’s amassed in the past five years. “I’m incredibly pessimistic and superstitious as a rule,” she said.

“Liz deserves everything she’s gotten. No one deserves it more,” the author Carmen Maria Machado said. Several years ago, the two started a group for women writers in Philadelphia, which includes Asali Solomon, Kiley Reid, Emma Copley Eisenberg and Sara Novic, among many others.

Machado went on: “Liz has this instinct for community. She’s incredibly generous. And she’s a deeply empathetic writer, which I think is her superpower.”

For the Peacock adaptation of “Long Bright River,” Moore brought her collaborative knack to the writers’ room. “It’s the closest experience I’ll have to being good at sports, because it is so much the product of a team,” she said.

The show was mostly filmed in New York City, but includes graffiti by Philadelphia artists and appearances by Kensington residents, including the head of the St. Francis Inn, the outreach organization where Moore used to lead writing workshops.

“I use 3 P’s as a handy teaching tool, but it’s also the way I write books,” Moore said. “Place comes first. Then people, then problems.”

With her Temple students, Moore is sanguine about the reality of a writing career.

“I say, I still have a day job and you probably will too,” she explained. “But hopefully you can find beauty in art outside of work. If that means keeping a journal in which you write once a week, that too is meaningful. It serves as a huge comfort to me to know that even if all of this goes away I will still have that, quietly, in my life.”

Secretary of State Marco Rubio estimated that he had signed perhaps more than 300 letters revoking the visas of students, visitors and others to force their expulsion from the United States because of their foreign policy views or criminal activities.

He has been signing letters daily to revoke visas since taking office in late January, Mr. Rubio told reporters on Thursday night aboard an Air Force passenger jet traveling between Paramaribo, Suriname, and Miami, where he lives with his family. Mr. Rubio was concluding a three-nation tour in the Caribbean and South America.

“I don’t know actually if it’s primarily student visas,” he said. “It’s a combination of visas. They’re visitors to the country. If they’re taking activities that are counter to our foreign, to our national interest, to our foreign policy, we’ll revoke the visa.”

He said he reviewed each case himself before signing off on actions that would be taken by immigration agents. Mr. Rubio said that a visa holder charged with a crime while in the United States should automatically lose their visa. He is also expelling permanent U.S. residents by stripping them of their green cards.

“My standard: If we knew this information about them before we gave them a visa, would we have allowed them in?” he said. “And if the answer is no, then we revoke the visa.”

Mr. Rubio declined to say how the cases arrived at his desk. “We’re not going to talk about the process by which we’re identifying it because obviously we’re looking for more people,” he said.

Mr. Rubio has been the most senior aide of President Trump involved in the contentious deportation efforts in communities across the United States. In mid-March, Mr. Rubio finalized a deal in which President Nayib Bukele of El Salvador agreed to accept U.S. deportation flights with more than 200 migrants, who were put into a prison there.

At least some of the migrants had fled to the United States from the repressive autocratic government of Venezuela and were not criminals, their lawyers say, but the United States failed to give them due process during their detention and deportation.

Mr. Rubio has also told the Homeland Security Department to detain students or recent graduates for deportation because of what he called their opposition to American foreign policy.

He told reporters on Thursday at a news conference in Georgetown, Guyana, that he had revoked the student visa of a Tufts University doctorate student and Fulbright scholar from Turkey. The student, Rumeysa Ozturk, was one of several authors of a student newspaper essay last year calling for university support of Palestinian rights and divestment from Israel.

After Mr. Rubio’s action, six people in black clothes and some wearing masks — presumably federal agents — seized her off a street outside her home in Somerville, Mass.

Mr. Rubio has also signed off on stripping the permanent residency status of two other students who were involved in pro-Palestinian protests at Columbia University: Mahmoud Khalil, born in Syria, and Yunseo Chung, born in South Korea.

Mr. Khalil, 30, is married to a U.S. citizen who was eight months pregnant when immigration agents seized him from their home in New York this month and took him to a detention center in Louisiana.

Ms. Chung, 21, has been in the United States since age 7 with her family.

Mr. Rubio has been named in separate lawsuits filed by Mr. Khalil and Ms. Chung, as well as other legal challenges to the visa and green card revocations and attempted deportations.

In Ms. Chung’s case, a federal judge ordered the Trump administration to halt its efforts to deport her.

Mr. Rubio has vigorously defended the actions when asked in recent days about them. He has avoided talking about details of each case but has described many of the people whose visas or green cards he has stripped as activists in movements whose participants have vandalized buildings, held disruptive rallies at universities and prevented other students from attending class.

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

He added, “I encourage every country to do that, by the way, because I think it’s crazy to invite students into your country that are coming onto your campus and destabilizing it.”

Critics say Mr. Trump and Mr. Rubio’s actions are similar to those taken by authoritarian governments that seek to suppress free speech and assembly.

On Thursday, Mr. Rubio was asked twice whether under his rationale, Chinese Communist Party officials and authorities in Hong Kong had the right to deport foreign students involved in the 2019 pro-democracy protests in Hong Kong. As a senator from Florida, Mr. Rubio supported the protests through legislation, even though some of the protesters’ actions disrupted campuses and public life.

On the plane, Mr. Rubio said, “Well, every country in the world can deny visas to whoever they want. It’s that simple. That’s a fact. Whether we like it or not, they can deny visas.”