The man authorities say is responsible for the shooting Saturday at Brown University that killed two students, as well as the murder of an MIT professor on Monday, has been found dead of an apparent self-inflicted gunshot wound, officials announced Thursday evening.

The suspect is Claudio Manuel Neves Valente, 48, a Portuguese national who police say obtained permanent lawful resident status in 2017 after using a student visa and later applying for a green card, Boston.com reported.

He was found dead in a storage unit with a firearm next to him, police said.

“Officials said they are still working to determine a motive for the shootings but indicated that Neves Valente likely acted alone,” the news outlet reported, adding:

Neves Valente was enrolled in a physics PhD program at Brown from the fall of 2000 until taking a leave of absence in April of 2001, Brown University President Christina Paxson said. He formally withdrew from the university in 2003, she told reporters Thursday night. 

“I think it’s safe to assume that this man, when he was a student, spent a great deal of time in (the Barus & Holley building) for classes and other activities as a PhD student in physics,” Paxson said. “He has no current active affiliation with the university or a campus presence.”

According to police, Neves Valente, whose last known address was in Miami, is also the man who shot and killed Nuno Gomes Loureiro, a nuclear science and engineering professor at MIT is is also from Portugal.

“Police say their case cracked open Wednesday night after a tip led them to a car linked to the suspect. That brought them to a Massachusetts car rental company that had images of him, and paperwork with his real name,” NPR reported.

According to Massachusetts U.S. Attorney Leah Foley, Neves Valente and Gomes Loureiro attended the same academic program in Portugal between 1995 and 2000 and knew each other.

Boston.com reported that after the Brown shooting, “Neves Valente rented the car in Boston, murdered Loureiro, changed his license plate, and drove to the storage unit in New Hampshire.”

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