US university killer's mystery motive sought after suicide

Claudio Neves Valente came to the United States as an ambitious physics student at Brown University, but ended his life while hiding from police after killing two students at the Ivy League institution as well as an MIT professor.

Authorities say Valente, a 48-year-old Portuguese national, shot dead Brown students Ella Cook and Mukhammad Aziz Umurzokov, and wounded several others, on December 13 before heading to the home of renowned Massachusetts Institute of Technology professor Nuno Loureiro and killing him two days later.