Claudio Neves Valente, the man who killed two Brown University students and an MIT professor last December, plotted the attacks over three years, federal investigators revealed. The Portugal native and legal permanent U.S. resident had been socially isolated, making his intentions difficult to track before the December shootings that claimed the lives of students MukhammadAziz Umurzokov and Ella Cook, and MIT physicist Dr. Nuno Loureiro.

Valente's victims were "symbolic in nature," representing his perceived personal failures and injustices, according to the FBI report. The 48-year-old purchased the weapons legally at a Florida pawnshop and died by suicide in New Hampshire. His transient lifestyle and lack of social support provided no opportunity for warning signs to be noticed, investigators noted, raising questions about how such isolated individuals can be monitored.

Brown University now faces lawsuits from three injured students who claim the school failed to provide adequate security. University officials said they would review the complaints carefully through the legal process. The incident highlights potential liabilities for educational institutions in preventing violence and maintaining campus security.