HARRISBURG, Pa. (AP) — Security guards at the federal courthouse in Harrisburg shot and wounded a knife-wielding man who attempted to attack one of them on Monday, authorities said.

Few details of Monday's shooting were immediately available, and authorities said the FBI was leading the investigation.

In a statement, the U.S. Marshals Service said the security officers moved to stop the man after he entered the courthouse, brandishing a knife.

The suspect attempted to attack one of the security officers before they shot him, striking him multiple times, the marshals service said.

He was in stable condition at a hospital, while the security officers were uninjured, the marshals service said.

The security officers are under contract with the marshals service to guard the courthouse.

Police also responded to the shooting, which happened inside the building in the first-floor lobby. The courthouse was closed afterward.