A bomb squad training exercise at a prison facility in Pennsylvania went wrong and resulted in multiple injuries to law enforcement officers.
Authorities confirmed that three law enforcement officers were injured at a Montgomery County prison on Thursday morning in an explosion during a training exercise.
The FBI said in a statement that a Pennsylvania State Trooper, a member of the Montgomery County Sheriff's Office, and an FBI agent were hurt in the blast.
Emergency responders including at least two fire engines responded to the incident in a field near SCI Phoenix prison just after 10am.
Pennsylvania State Police and the FBI are running a joint investigation into the incident, with the FBI saying that a training device had detonated unexpectedly.
The FBI said: "This morning, FBI Philadelphia was holding explosives response training at SCI Phoenix for law enforcement partners when a live training device unexpectedly detonated, wounding bomb technicians from the Montgomery County Sheriff's Office, Pennsylvania State Police, and FBI Philadelphia."
Authorities released no further details on the incident.