Federal and local authorities are investigating an intentional explosion that occurred early Saturday morning inside Harvard Medical School’s Goldenson Building in Boston’s Longwood Medical Area. The blast, reported at 2:48 a.m. on November 1, 2025, sent shockwaves through the campus’s research community and prompted a swift joint response from the FBI, Harvard University Police, and Boston emergency services.

According to officials, two masked men were seen fleeing the scene moments after the explosion on the building’s fourth floor. Surveillance images released later in the morning show the suspects running toward Longwood Avenue before disappearing from camera range. No injuries have been reported, and the explosion was confined to a single laboratory suite, but investigators have confirmed the device was deliberately detonated.

The FBI has now taken an active role in the investigation, working alongside Harvard police and the Boston Police Department. Agents are analyzing debris and chemical residues to determine the nature of the explosive used and whether the attack was meant to target specific research or personnel.

Authorities have not disclosed a motive, but the deliberate nature of the blast has sparked serious concerns about the security of biomedical and university research facilities nationwide. Officials are urging the public to submit any tips or footage that could help identify the suspects.

The Goldenson Building, home to advanced research in neuroscience and molecular biology, remains partially closed as safety inspections continue. Students and faculty have been advised to work remotely while damage assessments and forensic analysis proceed.

While no group has claimed responsibility, the attack comes amid a tense climate of growing ideological hostility toward elite academic institutions. Conservative commentators have long raised alarms about political radicalization within certain activist circles, though investigators have yet to determine whether ideology played a role in the incident.

Law enforcement sources have stressed that the investigation remains ongoing, with all leads under review. The FBI has set up a dedicated hotline for information related to the suspects, described as two males wearing dark clothing and face coverings.

For the Harvard community—and for universities across America—the explosion serves as a stark reminder of the vulnerability of critical research hubs to targeted acts of sabotage or intimidation. The quick containment of the incident prevented a potential catastrophe, but questions remain about how such an attack could happen in one of the nation’s most secure academic environments.