Harvard Medical School explosion appears intentional; two suspects sought, no injuries reported

An early-morning explosion inside a Harvard Medical School building jolted Boston’s Longwood campus on Saturday, November 1, in what investigators now believe was an intentional act. No injuries were reported, but the blast triggered evacuations, a multi-agency response, and a manhunt for two unidentified people seen fleeing moments before the detonation.

What happened inside the Goldenson Building

Shortly before 3:00 a.m. ET, a fire alarm drew a campus police officer to the Goldenson Building on Longwood Avenue. As the officer approached the floor where the alarm originated, two individuals ran from the area. The officer then found evidence of an explosion on an upper floor, prompting an immediate call for additional units and a sweep of the facility.

Specialized teams, including an arson unit, examined the scene and concluded the blast was likely deliberate. A precautionary search located no additional devices, and the building was secured pending further forensic work. By daybreak, the incident zone remained cordoned off while technicians documented blast patterns, collected residue samples, and mapped possible points of ignition.

What authorities are doing now

• Suspect search: Investigators are reviewing security footage from building entrances, adjacent corridors, and nearby streets to track the escape route of the two people who fled. Still images have been circulated to partner agencies.

• Forensics: Specialists are analyzing debris to determine whether a homemade device, chemical reaction, or a hybrid method produced the blast. Priority tests include traces of oxidizers, accelerants, and metallic fragment signatures that could indicate specific components.

• Campus security posture: Patrols have been augmented around labs and access-controlled areas. Expect ID checks and limited entry at some doors through the weekend.

What we know — and what we don’t

Confirmed

• Timeframe: Alarm activation and response occurred around 2:45–3:00 a.m. ET.

• Location: Interior of the Goldenson Building, part of the medical school’s research complex.

• Casualties: No injuries reported.

• Additional threats: None found during initial sweeps.

• Intent: Preliminary assessment indicates the explosion was intentional.

Unconfirmed / under investigation

• Motive: Unknown. Investigators are exploring possibilities from targeted sabotage to criminal mischief.

• Device type: Pending lab results; early on-scene findings are inconclusive.

• Connection to other incidents: No verified links so far.

Impact on campus operations

Morning activities in parts of the Longwood area were rerouted or delayed while responders completed safety checks. Research groups with space in or adjacent to the affected floors were asked to remain off-site until building managers complete structural and air-quality assessments. Essential functions—including critical equipment monitoring and temperature-sensitive storage—were supported by standby staff once the scene was declared safe to enter with escorts.

Students and staff should monitor official campus alerts for building-by-building guidance and any temporary badge-access restrictions.

Safety guidance for the campus community

• Report suspicious activity immediately. Use campus emergency numbers if you see unattended bags, unusual chemical odors, or tampering with doors, hoods, or electrical panels.

• Respect access controls. Do not hold doors open for strangers; ensure tailgaters badge in.

• Lab housekeeping matters. Secure solvents, oxidizers, and gas cylinders; confirm that chemical storage and waste labeling meet current standards.

• Know your exits. Review evacuation routes and the location of extinguishers and pull stations on your floor.

How the investigation typically unfolds

Incidents of this kind move through a forensic timeline: residue testing and fragment analysis in the first 24–72 hours; interviews and digital forensics (badging logs, network access timestamps, nearby license-plate scans) over the next several days; and a developing behavioral profile once investigators understand how the device or reaction was staged. If the suspects are identified, charges could range from malicious destruction of property to possession or use of an explosive or incendiary device, with penalties scaling to intent and damage.

What to watch next

• Public bulletin with suspect images: Authorities are expected to release clearer photos or descriptions once they refine the timeline and confirm camera angles.

• Building re-openings: A phased return is likely, starting with unaffected floors and spaces cleared by structural and environmental checks.

• Motive clarity: Lab results and interviews should narrow whether the act was targeted or opportunistic.

The Harvard Medical School explosion caused no injuries but appears to have been intentional, with two suspects at large. The area is secure, the building is under forensic review, and campus operations are adjusting while investigators work through footage, residue analysis, and tips. Expect visible security and periodic alerts as the inquiry moves from scene processing to suspect identification.