Ex-Brown Graduate Student Linked to Deadly Campus Shooting and Killing of MIT Fusion Leader, Authorities Say

On a cold Monday evening in December, the foyer of a brick apartment building in Brookline, Massachusetts, was nearly empty when a gunman stepped inside.

Neighbors later told police they heard a single sharp crack and the sound of someone falling. When officers arrived, they found 47-year-old Nuno F. G. Loureiro, an MIT professor and global leader in fusion energy research, bleeding on the floor near the entrance. He was taken to Beth Israel Deaconess Medical Center in Boston and died in the early hours of Dec. 16.

Two days earlier and 50 miles away, another set of gunshots had torn through a lecture hall at Brown University in Providence, Rhode Island. At first, police said there was no connection between the two crimes. Within days, investigators would say they were part of the same deadly spree, allegedly carried out by a former Brown graduate student who had once shared classrooms with Loureiro in Lisbon.

Authorities say the Dec. 13 mass shooting at Brown and the Dec. 15 killing in Brookline were the work of Cláudio Manuel Neves Valente, a 48-year-old Portuguese national who left Brown’s physics Ph.D. program more than 20 years ago and later reentered the United States on a diversity immigrant visa. The case has forced two elite universities to confront gaps in their security, and quickly spilled into national debates over guns, immigration and the impact of intense academic pressure.

A classroom attack and a vanished gunman

The first attack came on the afternoon of Saturday, Dec. 13, inside Brown’s Barus & Holley building, which houses engineering and physics classrooms.

Around 4 p.m., a teaching assistant was wrapping up an optional review session for a Principles of Economics final exam in room 166, a tiered lecture hall that seats nearly 200 students. As students began packing up, a man in dark clothing and a mask walked in and opened fire with two 9 mm Glock handguns, according to law enforcement and university officials.

He fired roughly 40 to 44 rounds, killing 19-year-old sophomore Ella Cook and 18-year-old first-year student MukhammadAziz Umurzokov, and wounding nine others.

“It was chaos,” one student later told local reporters. “People were screaming, hitting the floor, trying to get out any way they could.”

Brown officials say the first campuswide alert went out at 4:22 p.m., warning of an active shooter near Barus & Holley and instructing students to lock doors and shelter in place. About half an hour later, the university sent a second alert saying a suspect was in custody. That message was incorrect and was retracted roughly 20 minutes later.

A separate report of shots fired near another campus location, on Governor Street, prompted a second wave of panic. Brown later said that report was unfounded but kept its shelter-in-place order in effect because the original gunman had not been found.

Despite a heavily publicized network of more than 1,200 security cameras on and around campus, police did not obtain a clear image of the shooter’s face. Investigators say the attacker used a hallway with limited camera coverage, kept his mask on and quickly exited toward Providence’s residential streets. Neighborhood cameras captured a masked figure walking calmly away and even passing a responding police car.

Authorities initially detained a man in his 20s at a hotel in Coventry, Rhode Island, and seized firearms, but he was later cleared and released.

A suspect identified and misidentified

As police searched house to house and federal agencies joined the manhunt, an online search for the shooter moved faster — and in a starkly different direction.

Within hours, several right-wing commentators and activists began naming a Palestinian Brown student on social media as the gunman, posting his photograph and describing the attack as “Islamic terrorism.” One activist falsely claimed the shooter had shouted “Allahu akbar.” None of those claims were supported by police.

The student, who has not been publicly identified by major news outlets, was inundated with threats and abuse. Brown removed his profile information from public websites. Attorneys representing him later described the episode as “an unimaginable nightmare” driven by anti-Palestinian sentiment.

At a Senate Judiciary Committee hearing days later, Sen. Sheldon Whitehouse, a Rhode Island Democrat, urged people to stop spreading unfounded theories about the shooting. “For anyone listening who has been taken in by this nonsense,” he said, “please just knock it off.”

Behind the scenes, investigators were building a case around a different suspect.

A second killing and a shared past

On the evening of Dec. 15, Loureiro returned to his apartment building in Brookline, a town that borders Boston and is home to many MIT and Harvard affiliates. Surveillance footage reviewed by investigators shows a man matching Valente’s description near the building beforehand and entering the foyer, according to a federal criminal complaint.

Loureiro, a professor of nuclear science and engineering and physics at MIT and director of the school’s Plasma Science and Fusion Center, was shot shortly after he came through the door. At first, Massachusetts officials told reporters there was no known link between his killing and the Brown shooting.

Loureiro and Valente had known each other for decades, authorities later said. Both studied engineering physics at Instituto Superior Técnico, a top technical university in Lisbon, in the late 1990s. Former classmates have described Valente as exceptionally talented — and acutely conscious of it. One recalled to Portuguese media that he “graduated first in our class,” ahead of peers including Loureiro.

Valente enrolled in Brown’s physics Ph.D. program in 2000, but left on leave the following year and formally withdrew in 2003 without completing his degree. According to classmates quoted in European and U.S. outlets, he was deeply affected by the setback and by watching contemporaries, including Loureiro, go on to prominent scientific careers.

Loureiro earned a doctorate from Imperial College London, worked at leading fusion laboratories in the United Kingdom and New Jersey and joined MIT’s faculty in 2016. He became director of the Plasma Science and Fusion Center in 2024 and was widely seen as one of the world’s top theorists of plasma dynamics.

The Portuguese president, Marcelo Rebelo de Sousa, called his death “an irreplaceable loss for science.”

A trail through Boston and a storage unit in New Hampshire

In the days between the Brown shooting and the discovery of Valente’s body, investigators pieced together his movements from rental car records, hotel bookings, email and phone activity and surveillance footage.

According to law enforcement, Valente rented a gray Nissan Sentra with Florida plates from a Boston car agency in mid-November and was captured multiple times by automated license plate readers near Brown’s campus in early December. Staff at Brown later reported seeing a suspicious man loitering near Barus & Holley on at least two occasions before the shooting.

After the attack in Providence, records show, accounts linked to Valente logged in from internet addresses near Boston University. On Dec. 15, the day Loureiro was shot, those accounts connected from the Brookline area. Surveillance cameras later recorded a man in similar clothing entering a self-storage facility in Salem, New Hampshire, about an hour after the Brookline killing.

On Dec. 18, acting on a federal search warrant, agents entered the unit and found Valente dead from a self-inflicted gunshot wound to the head. Two Glock pistols were recovered inside. Ballistics tests later matched one pistol to shell casings at Brown and the other to casings in Loureiro’s building, according to federal and local officials. Preliminary DNA testing also tied Valente to evidence at the Providence scene.

An autopsy estimated that he had died on Dec. 16, the day after Loureiro was shot.

U.S. Attorney’s offices in Rhode Island and Massachusetts have said they believe Valente acted alone. With the suspect dead, no criminal trial will be held, and investigators have cautioned that they may never fully explain his motives.

Brown and MIT under the microscope

On Dec. 19, Brown President Christina Paxson formally identified Valente as the suspect in a message to students and staff and confirmed he had not been affiliated with the university since 2003.

“The news that the suspect in the Dec. 13 shooting has taken his own life does not erase the grief and fear that our community continues to experience,” she wrote, “but it does allow us to begin a path of repair, recovery and healing.”

Brown canceled remaining fall semester classes and exams, organized vigils and rolled out expanded mental health services. The university also announced a series of reviews: an immediate plan to upgrade building access and patrols, an independent after-action review of the shooting response and a broader campus safety audit that would examine camera coverage, door locks and emergency communication.

At the same time, the school’s police department came under sharp scrutiny. Brown placed its vice president for public safety, Rodney Chatman, on leave and hired former Providence police chief Hugh Clements as interim public safety leader.

Paxson has defended the timing of Brown’s emergency alerts, saying messages went to about 20,000 people within minutes of the first 911 calls. She acknowledged errors — including the incorrect announcement that a suspect was in custody — and said they would be a focus of the outside review.

MIT President Sally Kornbluth announced Loureiro’s death to the campus community in a separate message and urged colleagues and students to support one another.

“The facts we have now bring some measure of relief,” she wrote, referring to the end of the immediate threat, “but they also raise others that may never be properly answered.”

A national fight over visas and campus safety

As details of Valente’s background emerged, the case quickly moved from campus briefings into national politics.

Federal officials confirmed that Valente had become a lawful permanent resident in 2017 through the Diversity Immigrant Visa program, also known as the visa lottery, which offers a limited number of green cards each year to applicants from countries with historically low immigration to the United States.

Within days, President Donald Trump and Homeland Security Secretary Kristi Noem announced a halt to new diversity visa processing, with Noem calling the lottery a “disastrous program” and saying, “This heinous individual should never have been allowed in our country.”

Immigration advocates and some legal scholars argued that the administration was using an isolated crime to justify broader restrictions on legal immigration, and questioned whether the executive branch could suspend a program created by Congress without legislative action. Research consistently shows that immigrants are, on average, less likely to commit violent crimes than native-born Americans, but that data rarely cooled the debate.

The Department of Education separately opened a formal review of Brown’s compliance with the Clery Act, a federal law that requires universities receiving federal aid to disclose campus crime statistics and issue timely warnings of threats. Education Secretary Linda McMahon said investigators would examine Brown’s security infrastructure and its handling of emergency alerts, and ordered the university to submit extensive documentation by late January.

Trump publicly criticized the university’s security practices, posting on social media: “Why did Brown University have so few Security Cameras? … In the modern age, it just doesn’t get worse!!!” Brown has said it operates more than 1,200 cameras on and around campus, though administrators concede that older buildings like Barus & Holley had gaps in coverage that are now being addressed.

Questions that may never be answered

Nearly every major institution touched by the case — Brown, MIT, federal agencies and state police — has now issued reports, statements or investigations. Forensic evidence has tied the shootings in Providence and Brookline to a single suspect, and that suspect is dead.

Still, the most basic questions remain only partly answered.

Investigators have outlined how Valente moved between states, where he stayed, which weapons he used and which cars he rented. They have linked him to Loureiro through their shared past at a Lisbon university and to Brown through his brief, unfinished Ph.D. work.

They have not found, or at least have not released, any manifesto or recording that would explain why he targeted an economics classroom filled with undergraduates on Dec. 13, or why he allegedly sought out a former classmate turned fusion physicist two days later.

On Brown’s campus, room 166 in Barus & Holley has been scrubbed and reopened, now under tighter access controls. In Brookline, the foyer where Loureiro was shot again serves as a quiet passageway for residents coming home from work. At MIT and Brown, administrators and students pause at memorials to an economist-in-training, a first-year student and a scientist whose work reached around the world.

The man accused of killing them is no longer alive to face questions or judgment. The institutions and communities he left behind are still trying to understand how a former student who walked away from one campus more than two decades ago could return with guns, and what — if anything — could stop someone like him the next time.