"The Harvard University Police Department on Monday morning received an unconfirmed report that explosives may have been placed in four buildings on campus: the Science Centre, Thayer, Sever and Emerson Halls," a message on the University's website read.
"HUPD and Cambridge Police are on the scene. Out of an abundance of caution, the buildings have been evacuated while the report is investigated. Harvard's focus is on the safety of our students, faculty and staff. We will update the media when we have more information," it said.
Authorities with Cambridge Police Department and school officers descended on four sites at the Ivy League school that included it's science center and freshman dorms.
"Alert: Unconfirmed reports of explosives at four sites on campus," the school said in a Twitter message.
"HUPD and CPD are on the scene and investigating," read another tweet.
Students, faculty and staff were sent e-mails and text messages, alerting them to evacuate the buildings shortly after 9 am (local time), the New York Daily News reported.
The Harvard Crimson, the school's daily newspaper, tweeted that students erupted in cheers when officials announced that final exams scheduled for the day had been cancelled.
Sever Hall is a red-bricked building erected in the late 1800s that houses classrooms and lecture halls. Thayer Hall is a student dorm.
The Science Centre houses dozens of laboratories for multiple subjects, including astronomy, chemistry and physics. Emerson Hall, erected in 1905, serves as the home of the school's philosophy department.
The incident comes less than a month after Yale had a four-hour lockdown after an anonymous caller said his roommate was planning to shoot people on the campus.
State troopers from the K9 and bomb squads have responded to the scene, Massachusetts State Police said.
The main campus of the school, among the nation's most prestigious, sits on 210 acres in Cambridge. Harvard's student body includes about 6,700 undergraduates and another 14,500 graduate and professional students.
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