Portuguese physicist Nuno Loureiro, one of the world’s leading experts in nuclear fusion and director of the Massachusetts Institute of Technology’s Plasma Science and Fusion Centre, has died after being shot at his home in Brookline, Massachusetts, late on Monday night.

According to US media reports, Loureiro, 47, was found with multiple gunshot wounds and was rushed to a Boston hospital, where he was pronounced dead on Tuesday morning.

Police have launched a homicide investigation but have released no information about a suspect or possible motive. However, neighbours told local reporters they heard gunfire before alerting authorities.

Quoted by The New York Times, the US ambassador to Portugal, John J. Arrigo, expressed his condolences to Nuno Loureiro’s family, friends and colleagues in a statement on Tuesday.

“We honour his life, his leadership in science and his lasting contributions,” he said.

MIT president Sally Kornbluth issued a university-wide letter expressing “great sadness” over the death of Loureiro, whose survivors include his wife.

“This shocking loss for our community comes in a period of disturbing violence in many other places,” the institute’s president said.

The Instituto Superior Técnico (IST) in Lisbon, where the physicist graduated and conducted research, also released a statement recalling the “brilliant colleague with whom it was a scientific and personal pleasure to collaborate.”

Portugal’s President of the Republic also expressed his “deep sorrow” following the death of physicist and university professor Nuno Loureiro, calling the shooting a “shocking” act of violence that has deeply affected the academic and scientific community.

In a statement posted on the presidency’s website, Marcelo Rebelo de Sousa praised Loureiro’s intellectual rigour, his dedication to science and his significant contributions to physics. Beyond his professional achievements, the president highlighted Loureiro’s collaborative spirit, generosity in sharing knowledge, and commitment to scientific progress.

Calling his death an irreparable loss for science and all who worked with him, Marcelo offered heartfelt condolences to Loureiro’s family, friends, colleagues and the wider scientific community.

Born in central Portugal, Loureiro graduated in 2000 from the IST and completed his PhD at Imperial College London in 2005. After research roles at Princeton University and the UK’s Culham Centre for Fusion Energy, he returned to Portugal before joining MIT’s faculty in 2016.

He became director of MIT’s Plasma Science and Fusion Centre in May 2024—one of the university’s largest and most prestigious laboratories—and was widely regarded as a driving force in theoretical fusion research.

Loureiro earned multiple high-profile accolades, including the US National Science Foundation Career Award in 2017 and the Presidential Early Career Award for Scientists and Engineers, presented in 2025 by then-President Joe Biden.

He believed nuclear fusion could transform the world, once saying: “Fusion energy will change the course of human history.”