Virginian Mukhammad Aziz Umurzokov was remembered as an ambitious student who always went the extra mile for his friends.
FBI Boston Special Agent in Charge Ted Docks said he believes the gunman remains "armed and dangerous."
The Providence Police Department urged anyone who recognizes the man to call its Tip Center.
The FBI has offered a $50,000 reward for information on the killer.
When asked if the shooter was still in the area, the mayor responded that "honestly, we have no way of knowing."
An active shooter was first reported on the Ivy League campus shortly before 4:30 p.m.
