Security guards belonging to Harvard University and Cambridge police were at the scene trying to find out the bombs reported to be hidden.
Harvard University said in an emergency page on its website that the buildings were evacuated as a matter of abundant caution.
"Our focus is on the safety of our students, faculty and staff", the university said. While Thayer Hall is a dormitory for freshers, Harvard Science Center and Sever and Emerson halls are academic buildings.
