UPDATE (2:52 p.m.) - Harvard University officials say the Science Center is cleared, and that all four sites previously evacuated are now open.
UPDATE (1:00 p.m.) - Harvard University officials say Thayer and Emerson Hall are cleared and students may return; however, Sever Hall and Science Center are still closed.
(NECN: Eileen Curran, Cambridge, Mass.) - Four buildings at Harvard University have been evacuated after campus police received an unconfirmed report that explosives may have been placed inside.
School administrators have been updating the student body via social media and university website.
Administrators have confirmed that federal authorities are on the scene and are working with state and local police to investigate these unconfirmed reports of explosives.
According to the Harvard Crimson, no explosives have been found so far.
The threat came into Harvard University Police about 9 a.m. Monday targeting four buildings - the science center, academic buildings Sever and Emerson Halls, and residential dorm Thayer Hall. Three of the four buildings evacuated boarder Harvard Yard. Authorities have limited access to the yard.
Students were in the process of taking final exams when the threats came through and were evacuated to Annenberg Hall.
"I was actually supposed to be taking my LPSA final and just as the professor was reading the instructions, the fire alarm went off and he was just like, 'You guys all have to get out of the building,' and one of the cops was 'You should go somewhere warm, you're going to be here for a while,' so then we all just ended up going to the dining hall and we were there ever since," says one student.
Eileen Curran has more from students in the attached video.