When protests over the Gaza war took root on Columbia University's campus last spring, Mahmoud Khalil became a familiar, outspoken figure in a student movement that soon spread to other US colleges.
The international-affairs graduate student was a fixture in and around the protest encampment on Columbia's Manhattan campus, serving as a spokesperson and negotiator for demonstrators who deplored Israel's military campaign in Gaza and pressed the Ivy League school to cut financial ties with Israel and companies that supported the war.
"We want to be visible," Khalil said last April.
Now that visibility has helped make him the face of President Donald Trump's drive to punish what he calls antisemitic and “anti-American” campus protests. In the first publicly known arrest of the crackdown, federal immigration agents took Khalil, a legal US resident married to an American citizen, from his apartment Saturday and held him for potential deportation.
To Trump and his administration, Khalil's arrest is an opening move in a campaign to rid the country of foreign students accused of helping to make American campuses intimidating territory for Jewish students.
To civil rights advocates and Khalil's lawyers, his detention is an assault on free speech and an attempt to suppress pro-Palestinian views.
And to some who have worked alongside the 30-year-old graduate student at the protests and elsewhere, his arrest is a startling takedown of someone with diplomatic experience that he brought to bear in the charged days of the demonstrations.
"You couldn’t meet a kinder or nicer person to work with. He’s thoughtful. He’s intelligent. He’s conscientious," said former British diplomat Andrew Waller, a colleague of Khalil's from the UK’s Beirut-based embassy for Syria.
Khalil worked there from about 2018 to 2022, running a scholarship fund and supporting the UK’s diplomatic engagement with Syria, Waller said, noting that the role required an extensive background check.
He said the two spoke a few weeks ago, and Khalil was focused on becoming a father- his wife is pregnant- and on strife in Syria, where he was born and raised in a Palestinian family. Khalil also expressed concern that he might be targeted by the new Trump administration, Waller said.
After finishing high school in Syria, Khalil was on track to study aviation engineering there, but his plans were upended by the country's civil war, he wrote in a 2017 essay for an international education charity.
He recounted that he left for Beirut, got a job with an education nonprofit that helps Syrian children, and went to a Lebanese university.
"Where would I be if, like countless other Syrian refugees before me, I could not get a scholarship, could not work, or worst of all, could not leave Syria in the depths of the ongoing war?" he wondered in the essay.
Khalil earned a bachelor's degree in computer science and decided to continue his studies at Columbia, according to an online bio for a 2020 international development conference where he was listed as a speaker.
Then, last spring, protests over the war in Gaza erupted at Columbia, where demonstrators set up tents in the middle of campus and took over an administration building. A wave of similar demonstrations spread to some other colleges around the country.
Khalil served as a prominent student mediator on behalf of pro-Palestinian activists and Muslim students concerned for their safety.
But images of his maskless face at protests, along with his willingness to share his name with reporters, quickly made him a target among those who saw antisemitism in the demonstrations.
"I’m an easy scapegoat for them to say, 'Look at this Palestinian who never wore a mask and was active in the school protests,’" Khalil told the Associated Press last week.
The Columbia Jewish Alumni Association, meanwhile, has called Khalil a "ringleader of the chaos" on campus.
A new Columbia disciplinary committee has investigated various allegations against Khalil, most recently whether he violated a university anti-harassment policy by calling a dean "genocidal."
Khalil is now being held in a federal detention complex in Louisiana.