2 Massachusetts men arrested after explosion at Harvard Medical School, FBI says

BOSTON (AP) — Two Massachusetts men were arrested Tuesday in connection with a weekend explosion at Harvard Medical School, authorities said.

Logan David Patterson and Dominick Frank Cardoza face charges of conspiracy to damage by means of fire or an explosive, according to the charging document. Patterson, an 18-year-old from Plymouth, and Cardoza, a 20-year-old from Bourne, were arrested Tuesday morning and were due to be arraigned in federal court later in the day.

The explosion occurred early Saturday on the fourth floor of Harvard Medical School’s Goldenson Building. No one was injured. The building houses labs and offices associated with the school’s neurobiology department.

“Anxiety levels naturally rise when the public learns that an explosion was intentionally caused. I would say those levels may rise even higher in the Boston area,” U.S. Attorney Leah B. Foley said at a news conference, noting that the investigation is ongoing but that there’s no further threat to the university.

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According to the charging document, witnesses stated the two men were visiting Wentworth College for Halloween activities. Surveillance footage captured Patterson and Cardoza walking toward the Harvard Medical School. Witnesses said the pair chose the building because it looked abandoned. They also said the pair gained access to the building via the roof, the charging document states.

Medical school officials said the explosion caused no structural damage and that all labs and equipment remained intact. The Boston Fire Department determined that the explosion was intentional. Police said officers did not find additional devices during a sweep of the building.

An officer who responded to a fire alarm that morning encountered two people running from the building, university police said.