A source says 19-year-old Miles Pfeffer was stabbed Thursday night in the Curran-Fromhold Correctional Facility.
Pfeffer is hospitalized in stable condition. No further details were immediately available.
"We cannot comment on an incident that is under investigation," Philadelphia Dept. of Prisons officials said in a statement.
Pfeffer is being held behind bars without bail pending his trial.
The Buckingham Twp., Bucks County resident is charged with the murder of 31-year-old Sgt. Christopher Fitzgerald.
Fitzgerald, a married father of five, was killed at 17th and West Montgomery Avenue in North Philadelphia while investigating reports of a robbery in February 2023.
Fitzgerald was chasing three suspects after a series of robberies and carjackings in the area. After two of the suspects hid, officers say, Fitzgerald caught up with Pfeffer and ordered him to the ground. The pair struggled, and Pfeffer shot him six times, killing him, officials say.
Pfeffer, then 18, was arrested the next morning at his mother's suburban home and charged with murder, killing a police officer, carjacking and other crimes.
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