NEW YORK, Dec 19, 2025 (BSS/AFP) - A man believed to be behind both a mass shooting at Brown University and the killing of an MIT professor has been found dead after a days-long manhunt, authorities said Thursday.

The suspect, Claudio Neves Valente, was a 48-year-old Portuguese national who had once studied physics at Brown, officials announced at press conferences in Providence and Boston.

There was no immediate indication of a motive in the twin shootings at two of the top universities in the United States, which rattled the elite New England campuses.

The shooter's body was found at a storage unit in New Hampshire along with two firearms. He died by suicide, Providence police chief Oscar Perez said.

Neves Valente, who had been a permanent US resident since 2017, is believed to have acted alone.

"Tonight, our Providence neighbors can finally breathe a little bit easier," Mayor Brett Smiley told reporters.

On December 13, the shooter burst into a building at Brown, an Ivy League school in Rhode Island, where students were taking exams, and opened fire, killing two and wounding nine.

The victims were Ella Cook, vice president of Brown's Republican Party association, and Mukhammad Aziz Umurzokov, originally from Uzbekistan, who had hoped to become a neurosurgeon.

Six of the wounded were still in hospital in stable condition, and three have been released, university president Christina Paxson said in a statement late Thursday.

Then on December 15, Nuno Loureiro -- a physics professor at the Massachusetts Institute of Technology -- was fatally shot in his home in Brookline, in the greater Boston metro area.

For days, investigators appeared to have little to go on, releasing images of a person of interest and an individual who was seen standing near that person in an effort to trace them.

Officials had given daily media updates at which they voiced increasing frustration with the fruitless manhunt.

But then the case blew open thanks to a trail of financial data and video surveillance footage gathered at both scenes.

- 'Hiding his tracks' -

"The groundwork that started in the city of Providence...led us to that connection," Perez said.

In Boston, federal prosecutor Leah Foley, the US attorney for Massachusetts, explained how Neves Valente had been "sophisticated in hiding his tracks."

He switched the plates on his rental vehicle at one point and was using a phone that investigators had difficulty tracking, but eventually the pieces started falling into place.

Authorities initially detained a different man in connection with the shooting but later released him.

The university has faced questions, including from President Donald Trump, about its security arrangements after it emerged that none of its 1,200 security cameras were linked to the police's surveillance system.

There have been more than 300 mass shootings in the United States so far this year, according to the Gun Violence Archive, which defines a mass shooting as four or more people shot.

Attempts to restrict access to firearms still face political deadlock.

"Nothing can fully bring closure to the lives that have been shattered by last weekend's gun violence," said Paxson, Brown's president.

"Now, however, our community has the opportunity to move forward and begin a path of repair, recovery and healing."