Federal investigators announced Wednesday that a key phase of the sweeping investigation into the Brown University mass shooting and the killing of an MIT professor has closed.
Authorities said they have concluded the shooter acted alone in both attacks, that the victims were “symbolic in nature” and that he was able to plan for years without detection. Federal officials also cited his extreme social isolation, mental health issues and lack of meaningful ties to others.
The announcement comes as questions from the public — and from Brown University students shot and wounded in the attack — continue to linger over how years of violent preparation went unnoticed…