Officials investigate 'intentional' explosion at Harvard University medical building that left no injuries

An apparently "intentional" explosion at a Harvard University medical building early today is under investigation, authorities said.

An officer responded to the Goldenson building about 2:48 am local time and saw two people fleeing the building after a fire alarm was activated, according to the Harvard University Police Department.

On the building's fourth floor it was apparent there had been an explosion – one that an arson team has initially assessed "appeared to be intentional," police said.

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Boston police swept the building for "any additional devices" but none were found, and no injuries were reported, officials said.

"The Harvard University Police Department is actively investigating this incident in coordination with local, state, and federal law enforcement partners," university police said.

Officials did not provide details on the nature of the explosion or any damage that may have resulted.

CNN has reached out to the Boston police and fire departments for additional information.

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