Brown University shooter made multiple trips to Boston for surveillance before deadly attack: sources

Brown University shooter Claudio Neves Valente took at least four trips up to Boston this year, with each visit getting longer than the last, The Post has learned.

He also engaged in an extensive amount of pre-planning and surveillance, a law enforcement source told The Post.

Valente had long simmering personal grievances over past personal failures at Brown, the source said.

The former physics student enrolled in a PhD at the Ivy League school but left after one year.

His first trip to Boston from Miami lasted three days between Feb. 12 and Feb. 15.

That spring, he took a 17 day trip, between April 8 and 25.

In the fall, he went up for 21 days, between Oct. 26 and Nov. 16, and quickly returned for a nine day trip, between Nov. 17 and 26.

Here’s the latest on the mass shooting at Brown University

• Brown, MIT shooter’s ties to school, professor go back 30 years as timeline reveals potential clues before massacre
• Brown University shooter cased campus for weeks before massacre, custodian told cops
• Brown shooter made disturbing ‘barking noise’ as he gunned down students in classroom: witnesses
• Shootings at Brown University, MIT ‘cracked’ by homeless hero now ‘entitled’ to $50K reward: feds

He flew again to Boston on Dec. 1, authorities have said.

On Dec. 13, Neves Valente carried out his sick scheme, killing two students and injuring nine others before murdering MIT professor Nuno Loureiro two days later.