State police at Clearfield said Saturday an inmate at the Houtzdale state prison allegedly assaulted another inmate around 1 p.m. Friday.
Police said Lawrence Edward Peterson Jr., 43, was charged with aggravated assault.
Police said said the incident occurred as Peterson and the 59-year-old victim returned to their cell after completing a work assignment.
The two were cellmates.
Police said Peterson then began punching and kicking the victim in the head and shoulder area.
The victim reportedly suffered severe head injuries and was airlifted to UPMC Altoona.