Two individuals have been charged following an explosion at Harvard Medical School’s campus over the weekend, according to WWLP.

Authorities arrested Logan David Patterson, 18, and Dominick Frank Cardoza, 20, on Tuesday. Both face charges of conspiracy to cause damage using fire or an explosive device.

Surveillance footage captured at approximately 2:23 a.m. EDT on Saturday shows the suspects walking along Huntington Avenue and Longwood Avenue in Boston, heading towards the Harvard Medical School campus. The duo, who wore face masks and dark attire, were reportedly igniting Roman candle fireworks.

Once at the campus, the suspects allegedly breached a chain-link fence surrounding a construction site near the Goldenson Building. They then scaled scaffolding to reach the building’s rooftop. Campus police responded to a fire alarm triggered around 2:45 a.m., following an explosion on the fourth floor of the Goldenson Building, which houses a research laboratory in the Department of Neurobiology.

Investigators believe the explosion was caused by a large commercial firework, detonated inside a wooden locker within the lab.

During a news conference to announce the arrests Tuesday, FBI Boston Special Agent in Charge Ted Docks called the detonation an “extremely dangerous act that could have resulted in casualties had the Goldenson Building been occupied at that time.”

Police say security footage cameras captured the suspects visiting the fifth floor of the building between 2:45 and 2:50 a.m. before they left through a first-floor emergency door, escaping in the opposite direction. No one was hurt in the blast.

“This explosive device had the potential to cause significant injury to anyone nearby,” Docks said. “Only by sheer luck and because of a rapid response of first responders, no lives were lost, no one was injured and property damage was limited.”

Cardoza, of Bourne, was allegedly captured by surveillance sitting on a bench, removing his pants, and putting them in a nearby garbage bin.

Nearby surveillance at the Wentworth Institute of Technology allegedly captured Patterson, of Plymouth, intermittently running between buildings and trying to enter a residential campus building before being let in by a passerby.

Investigators say that Patterson left the building around 3:40 a.m. to meet up with Cardoza and a third person. The trio allegedly tried to enter another residential building before toward the Massachusetts College of Art and Design campus.

Authorities say Patterson could then be seen taking off his sweatpants and sweatshirt as the three suspects walked along Huntington Avenue. Witnesses would later tell investigators that Patterson and Cardoza had attended Halloween social events at Wentworth College.

The suspects will appear in federal court in Boston on Tuesday.

“Setting off an explosive device inside a locker at an institution geared toward higher education is not some harmless college prank,” Docks said. “It’s selfish, it’s short-sighted and it’s a federal crime.”

Law enforcement continues to investigate this incident and analysis of the explosive is ongoing.