Authorities are looking for suspects seen fleeing after a campus explosion in a Harvard Medical School building that police describe as “intentional.”

No one was hurt in the blast, which occurred early Saturday morning, the Harvard Crimson reported.

“The explosion took place on an area of the fourth floor of Goldenson, a Harvard Medical School building on the school’s main quad. An officer who responded shortly before 3 a.m. observed two individuals fleeing the building,” the student newspaper reported.

“…HUPD sent a subsequent email to Harvard affiliates shortly after 5 p.m. asking for assistance identifying two men, who they described as suspects. The images were captured on security footage. Both men are shown wearing sweatshirts with hoods and ski masks.”

The Boston Fire Department Arson Unit determined the blast appeared to be intentional, News 19 reported.

In a message to the campus community, Dean of the Faculty of Medicine George Daley stated: “First and foremost, we want to reiterate that thankfully no one was injured. The small section of the fourth-floor hallway where the explosion took place has been cleared and is fully operational. There was no structural damage to the building, and all labs and equipment remain intact.”

He added police have confirmed there is no continued public safety threat.

Harvard released three surveillance stills depicting two suspects and is asking anyone with information on the explosion or who knows the suspects pictured to contact detectives, the Boston Herald reported.

The images are grainy but appear to show two white males.

According to the New York Times, the “building appears to hold portions of the neurobiology department … [but] officials have not indicated what motive, if any, was behind the explosion.”

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