A coroner says a guard killed at a federal prison in northeastern Pennsylvania suffered blunt head and neck trauma and multiple stab wounds and cuts.

Lackawanna County Coroner Timothy Rowland says Monday night's death of Eric Williams is a homicide. An autopsy was performed Tuesday.

Prison officials say the 34-year-old corrections officer was working in a housing unit when an inmate attacked him with a homemade weapon. Authorities have not identified the prisoner involved.

Williams is the first federal prison guard in nearly five years to be killed on the job.

The high-security Canaan penitentiary is about 20 miles northeast of Scranton.