The four buildings that were evacuated on Harvard University's campus Monday morning have been searched and reopened for students after initial reports said explosives were planted in the buildings, the Boston Globe reported.

Just before 1 p.m. the school announced that Thayer hall and Emerson hall, two of the four buildings evacuated - were cleared. An hour later the university announced that Sever Hall had been reopened. Around 2:45 p.m., the university announced that the science center had also been reopened.

"It is a serious matter. We've seen in the past year with the Boston bombings that things like this are not supposed to be taken lightly," third-year student David Bicknell told MSNBC. "It's just a sense of unease."

Cambridge, Mass., police told MSNBC that the threat came in by email.

The school alerted its students with text messages at 9:08 a.m. and then posted alerts on its Web pages shortly after 9:33 a.m. telling everyone to evacuate the four impacted buildings, the Boston Globe reported.

Harvard University police, officers with Cambridge Police Department descended on the four sites, sweeping the buildings for explosives. Transit Police departments and bomb squad officers were also sent to the campus with bomb sniffing dogs, Reuters reported.

Shortly before 12 p.m. the school announced that federal and state officials had joined the probe.

According the Boston Globe, final exams for Harvard University students are scheduled for this week for undergraduates.

After hearing about the threat, Harvard officials postponed its morning finals.

College officials told the Boston Globe they were working to identify and reschedule exams that were slated for this morning within the three academic buildings. They also to make an announcement about the impact on afternoon exams as soon as possible, a university spokesman said in an e-mail to the Boston Globe.

A White House Official told The Boston Globe that President Barack Obama was briefed about the events taking place at his alma mater this morning.

"We continue to encourage the public to follow directions from the local officials. The White House will remain in touch with our federal, state, and local partners and the president will continue to receive briefings as needed," the official said.

Thayer hall is a freshman dormitory and the other halls are academic buildings. They are all located inside the ancient Harvard Yard section of the campus. The science Center is located just outside the yard.