Suspect in Brown University Shooting Worked in Portugal After Leaving University

Claudio Neves Valente was like a ghost.

He dropped out of Brown University in the early 2000s, and friends and family have said they had no idea what happened to him until he appeared two decades later, accused of killing two students at Brown University and a Massachusetts Institute of Technology professor this month.

Now, law enforcement officials are piecing together his life in the intervening years and trying to understand what drove him. But Mr. Neves Valente, once known for his intelligence as a young student, led what appears to have been a quiet and disconnected life once he left the university, making his path difficult to track.

Friends and family said they had lost touch with him, and few neighbors recalled his presence. He left few records or traces on the internet.

Originally from Portugal, Mr. Neves Valente was estranged from his family there. But after he left Brown in the spring of 2001, it appears he returned to his home country, where he worked for a major Portuguese internet services provider known as SAPO. He was employed at the Lisbon-based company between 2010 and 2013, according to a spokeswoman for MEO, a telecommunications firm that owns SAPO.

Mr. Neves Valente obtained a visa to come to the United States in 2017, and a police affidavit suggests that he at some point lived north of Miami, in a region with a tight-knit Portuguese community. But his neighbors there, including the owner of the house where he was said to have lived, said they did not remember him.

Amiel Sribman, 49, who lives next door to a house in north Miami that is listed as Mr. Neves Valente’s address by the authorities, said he did not see Mr. Neves Valente coming or going from the house, noting it was the only rental property in an area where most people own their homes.