Intentional blast at Goldenson Building under investigation

An explosion tore through a fourth-floor area of the Goldenson Building at Harvard Medical School on the Longwood medical campus in Boston in the early hours of Saturday, authorities said. A Harvard University Police Department officer responding to a fire alarm at about 2:48 a.m. found two unidentified people fleeing the building and later determined that a device had detonated on the fourth floor, university officials said. No injuries were reported.

Harvard and Boston fire officials said the Boston Fire Department Arson Unit assessed the blast as intentional. The Boston Police Department conducted a sweep of the building and reported finding no additional devices. The Federal Bureau of Investigation is assisting the Harvard University Police Department in the ongoing investigation, an FBI spokesperson said.

According to the university statement, the officer attempted to stop the two individuals but was unable to do so before proceeding to the floor where the alarm had been triggered. Responders secured the immediate area and the arson unit led an initial on-scene forensic assessment. University and city law enforcement officials are continuing investigative work, and campus...