The stabbing happened at the Curran-Fromhold Correctional Facility, located at 8101 State Road in Philadelphia around 1:40 p.m.
An inmate stabbed the guard once in the left arm, according to PPD.
"The guard was transported by Medic 49 to Jefferson-Torresdale Hospital, where they were placed in stable condition," the police wrote in the release.
The scene was being held, but no weapon was recovered.
The offender has been detained, and the investigation is ongoing with Northeast Detectives.
Check back here for possible updates on this developing situation.
Click here to follow Daily Voice Ambler-Blue Bell and receive free news updates.