'Intentional' explosion on Harvard medical school campus probed by FBI, 2 people seen fleeing building: police

The FBI is investigating after an "intentional" explosion inside a building on Harvard University's Longwood medical school campus early Saturday.

Harvard officials told Fox News Digital that just after 2:45 a.m., a Harvard University Police Department (HUPD) officer was dispatched to the Goldenson building at 220 Longwood Avenue in Boston for a fire alarm activation.

When the officer arrived, they saw two people fleeing the building, officials said.

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The officer tried to stop the pair before proceeding to the fourth floor where the alarm was triggered, finding an explosion had occurred.

The Boston Fire Department Arson Unit responded and made an initial assessment that the explosion appeared to be intentional, officials said.

The Boston Police Department conducted a sweep of the building to check for any additional devices; none were found.

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No injuries were reported in connection to the explosion.

"The Harvard University Police Department is actively investigating this incident in coordination with local, state, and federal law enforcement partners," a university spokesperson told Fox News Digital.

FBI Boston confirmed to Fox News Digital it is at the scene assisting HUPD, but referred any additional inquiries to university police.

Anyone with information about the incident should contact the Harvard University Police Department's Detective Bureau at 617-495-1796.

HUPD did not immediately respond to additional inquiries from Fox News Digital.

This is a developing story. Please check back for updates.