Nuno F.G. Loureiro, a 47-year-old physicist and fusion scientist, was shot Monday night at his home in Brookline, Massachusetts. He died at a local hospital on Tuesday, the Norfolk District Attorney’s Office said in a statement.

The prosecutor’s office said no suspects had been taken into custody as of Tuesday afternoon, and that its investigation was ongoing.

Loureiro, who joined MIT in 2016, was named last year to lead MIT’s Plasma Science and Fusion Center, where he aimed to advance clean energy technology and other research. The center, one of the school’s largest labs, had more than 250 people working across seven buildings when he took the helm.

Loureiro, who was married, grew up in Viseu, in central Portugal, and studied in Lisbon before earning a doctorate in London, according to MIT. He was a researcher at an institute for nuclear fusion in Lisbon before joining MIT, it said.

“He shone a bright light as a mentor, friend, teacher, colleague and leader, and was universally admired for his articulate, compassionate manner,” Dennis Whyte, an engineering professor who previously led MIT’s Plasma Science and Fusion Center, told a campus publication.

The president of MIT, Sally Kornbluth, said in a statement that Loureiro’s death was a “shocking loss.”

The homicide investigation in Brookline comes as police in Providence, Rhode Island, about 50 miles away, continue to search for the gunman who killed two students and injured nine others at Brown University on Saturday. The FBI on Tuesday said it knew of no connection between the crimes.

A 22-year-old student at Boston University who lives near Loureiro’s apartment in Brookline told The Boston Globe she heard three loud noises Monday evening and feared it was gunfire. “I had never heard anything so loud, so I assumed they were gunshots,” Liv Schachner was quoted as saying. “It’s difficult to grasp. It just seems like it keeps happening.”

Some of Loureiro’s students visited his home, an apartment in a three-story brick building, Tuesday afternoon to pay their respects, the Globe reported.

The U.S. ambassador to Portugal, John J. Arrigo, expressed his condolences in an online post that honored Loureiro for his leadership and contributions to science.

“It’s not hyperbole to say MIT is where you go to find solutions to humanity’s biggest problems,” Loureiro said when he was named to lead the plasma science lab last year. “Fusion energy will change the course of human history.”

Immigration enforcement agents have become a common fixture around courthouses in Massachusetts this year — plainclothes officers idle outside in black cars, chat with clerks and monitor hearings to find people to arrest.

While lawyers say U.S. Immigrations and Customs Enforcement has long apprehended immigrants at courthouses, the numbers have ballooned under the second Trump administration.

In the past, “You didn’t have a sense that immigration was always in the building. Now it’s like that’s the first thing you think about,” said public defender Antonio Vincenty.

The increased presence is not only in federal courts, but also at dozens of district courthouses in the state. Vincenty handles cases in East Boston, Chelsea and downtown Boston, and said he has had three clients arrested in court this year.

“We want those that commit crimes to be punished. I don’t think any criminal lawyer feels differently,” Vincenty said. “But we want the system to work. We want the system to live up to its rules — to treat people with fairness, to treat people with justice and due process.”

Courthouse arrests in Massachusetts have surged nearly three-fold over Trump’s first nine months in office, according to ICE data compiled by the Deportation Data Project at the University of California Berkeley School of Law.

A WBUR analysis of the data found 386 arrests at 46 courts across the state — including 147 at the federal courthouse in Boston — from January through mid-October. That’s up from 131 over the same period last year under the Biden administration.

And the latest data is almost certainly an undercount. In East Boston, for instance, ICE recorded only six courthouse arrests, while lawyers and immigration advocates report having seen far more.

Suffolk County District Attorney Kevin Hayden said ICE activity has impacted hundreds of cases prosecuted by his office — noting instances in which defendants got detained during proceedings, as well as times when victims and witnesses were afraid to cooperate because of agents’ presence.

“The ultimate concern is that it has a chilling effect on our ability to deliver public safety for victims and witnesses of crime,” Hayden said.

He acknowledged ICE has legal authority to operate in courts here, but, “Do I wish they would stay out of our courthouses?” he said. “Absolutely.”

“Do I wish they would stay out of our courthouses? … Absolutely.”

Suffolk County District Attorney Kevin Hayden

Assistance for ICE in East Boston

With immigration enforcement mounting, the Massachusetts Trial Court released a policy in May on how court staff are to interact with ICE. Court officers must provide public information to agents when asked — as that information is available to the public — but they can’t initiate communication with ICE.

According to the court rules, agents can enter court lockups to take people into custody, but court staff cannot assist in, nor impede ICE arrests. That was put to the test on the afternoon of Nov. 21 in East Boston — in an alley behind the district court — after Alejandro Orrego Agudelo’s arraignment.

Video taken by an immigration advocate in East Boston and shared with WBUR showed Orrego on the ground — shirtless, barefoot and shackled. Orrego cried out for help as two agents in black hoodies and blue jeans struggled to control him.

A crowd began to form, and a court officer in a white shirt and court badge helped the agents subdue the 27-year-old. At one point, the officer helped shove him into the back of a black SUV.

A woman in the crowd shouted: “Where are you taking him? He was released in court.”

One of the agents responded: “He needs to go to immigration court.”

Sandy Wright, a volunteer with the LUCE Immigrant Justice Network of Massachusetts, was off camera, challenging the second court officer: “Who do you work for? Are you Trial Court? I thought you’re not supposed to be cooperating with ICE.”

In the video, a second court officer stood before the crowd with her hand up, signaling the crowd to stop, and made a phone call: “This is East Boston district court, we need assistance from Boston Police Department. We have ICE here collecting somebody and we have a large crowd.”

Nine Boston police officers arrived on the scene that day. The police report said Orrego was “violently resisting the agent.” The video showed him struggling, with his hands and feet cuffed.

Orrego was in court facing charges that included assault and battery on a police officer and resisting arrest, as well as malicious destruction of property and disturbing the peace. He’d been arrested that morning after a neighbor called police to report an altercation with him. A communication with court officials shared with WBUR says ICE had a “detainer” to take him into custody.

But the incident represented a violation of the Massachusetts Trial Court’s policy not to help in an ICE arrest, according to Trial Court spokeswoman Jennifer Donahue.

She said in a statement, “Measures are being taken to address this violation.”

Donahue said the East Boston incident prompted the Court’s security leadership to meet with court officers across the state to reinforce its policy to neither help nor impede ICE arrests. She would not say if anyone has been disciplined for the violation.

The Executive Office of the Trial Court declined requests to interview Chief Justice of the Trial Court Heidi Brieger, who oversees all departments, and Trial Court Administrator Thomas Ambrosino.

Some scoff at measures that limit collaboration between court staff and ICE.

Retired ICE agent Albert Orlowski worked in immigration enforcement for more than two decades. He questioned how court officers could stand by while federal agents struggle to apprehend someone who’s resisting.

“Law enforcement agencies should cooperate with each other,” Orlowski said. “Assisting another officer — that’s called professional courtesy.”

The rationale for courthouse arrests is clear, Orlowski explained: It’s an obvious place to find people facing criminal charges, and it’s safer than most locations, as suspects typically have had to pass through metal detectors.

“It’s so much easier to arrest somebody from a courthouse — when they’re in a controlled environment — than it is to arrest somebody out on the street,” Orlowski said.

Spokespeople for Boston-area ICE and the Department of Homeland Security in Washington D.C. did not respond to requests for comment.

Evading ICE at courthouses

In a separate incident at East Boston District Court in late November, an 18-year-old high school student appeared for a summons. WBUR is referring to him by his middle name, Josué, as he fears retaliation by ICE.

Josué said the judge first heard the cases of non-Latinos, then called matters involving Latinos, all of whom spoke Spanish and required an interpreter. That’s when ICE agents showed up.

Local advocates outside the courthouse that day said ICE arrested at least two people during the proceedings. Josué said as he waited for his case to be called, he could hear the commotion and it was clear people were being grabbed as they left the court. He said he was afraid the agents would arrest him.

“For sure,” he said in Spanish. “But thank God, no.”

Josué said he’s undocumented and has been in the U.S. since he was 15.

When he walked out of the courthouse, Josué said the agents were distracted detaining someone else, and he managed to get into a car waiting around the block. Now he’s trying to keep his head down — he wants to finish high school, and not think too much about getting sent back to Honduras.

“God willing, that won’t happen,” he said.

ICE reported the highest number of Massachusetts district court arrests in Lynn, Woburn, Framingham and Waltham. At the Waltham District Court, west of Boston, an auto repair shop has a front row seat on the action.

Manuel Arias owns the shop across from the courthouse. He recounted seeing at least a dozen ICE arrests over the last few months as people left in cars or on foot. Arias said his staff filmed a number of the arrests, but they’ve become so commonplace that the mechanics stopped taking video.

“The way people have been grabbed has been savage,” Arias said in Spanish. Often, multiple agents grabbed a single person, he said.

In one case, a man bolted from the courthouse, he recalled, then ran across a busy intersection and got away.

Video from Arias, reviewed by WBUR, showed an agent giving chase, then giving up after the man jumps over a guardrail.

Calls for more restrictions on ICE activity in courthouses

In front of the Waltham courthouse steps, there are signs taped to lampposts: “ICE took our neighbor from this spot.”

“Unfortunately our courthouse has become an ICE trap,” said Jonathan Paz, founder of a group called Fuerza Community Defense Network, which monitors ICE activity in the city.

The group’s volunteers have witnessed dozens of ICE arrests in Waltham, Paz said. And in his view, the court system is bolstering the work of agents.

“Why [are] our taxpayer dollars, here in Massachusetts, being used to facilitate and better carry out these arrests in our courthouse?” Paz said.

“It’s remarkable to see just how complicit this whole system is.”

This week, the 32-year-old Waltham resident announced he’s running for Congress. He’s among those calling on the state to put more limits on ICE activity at courthouses.

Paz said he’s waiting for the Trial Court — or the Legislature, or the governor or the attorney general — to keep ICE from interfering with people’s legal proceedings. They can’t stop agents from being on court property, but they can take steps to help people have their day in court without fear of being arrested.

ICE’s policy on courthouse arrests dictates that agents must observe local laws. Some states require agents to present judicial warrants; Massachusetts requires only a form known as a detainer, signed by an ICE officer.

State Sen. Lydia Edwards, of East Boston, co-chairs the Legislature’s judiciary committee. She said she’s in contact with court officials about the spate of ICE arrests, and is considering whether to propose rules requiring agents to present a warrant signed by a judge. A similar initiative was recently enacted in Illinois, as well as in Connecticut.

“While we require a civil detainer, I think it’s worth us talking to the courts about what it means to require a judicial warrant,” Edwards said.

Edwards said any solution — even a state law — should have buy-in from court officials if it’s going to be properly implemented.

Another suggestion, she said, is to broaden access to remote hearings. Not having to go to a courthouse means ICE can’t arrest you there.

“I would love nothing more than for our courts to be a welcoming, safe place for justice, regardless of your immigration status,” she said. “That’s what I want.”

WBUR’s Patrick Madden contributed to this story.

A Massachusetts man is facing charges after a wrong-way crash that killed a New Hampshire resident last week.

The crash happened around 9:49 p.m. Friday on Route 128 in Danvers. A Hyundai Elantra was traveling in the wrong direction when it hit a Nissan Sentra on the southbound side of the highway.

A passenger of the Sentra, identified as 58-year-old David Mackey of Sandown, New Hampshire, was pronounced dead at the scene.

The Elantra’s driver, 42-year-old Jerry Andujar Bodden of Haverhill, is charged with motor vehicle homicide by reckless operation and improper operation of a vehicle, the Essex County District Attorney’s Office said, adding that prosecutors intend to bring more charges for allegedly operating under the influence of alcohol.

Bodden pleaded not guilty at an arraignment Monday in Salem District Court, according to prosecutors.

Judge Randy Chapman ordered Bodden held on $50,000 bail. Conditions include a monitored bar on alcohol consumption, GPS monitoring and home confinement with the exceptions of work, legal and medical appointments, prosecutors said. He is also prohibited from driving while the case is ongoing.

Bodden is due back in court Jan. 21, according to the district attorney’s office.

The highway was shut down for several hours for the investigation but has since reopened.