(Reuters) - A guard and an inmate at a Pennsylvania prison died after falling five stories down an elevator shaft following an altercation, media reported.

The inmate at Luzerne County Correctional Facility, in the city of Wilkes-Barre, was identified as Tracy Gilliam, 27, who was incarcerated for failing to register as a sex offender, the Times Leader newspaper reported, citing county officials. The identity of the prison guard was not disclosed.

The guard and inmate were killed on Monday following a brief altercation, Luzerne County Manager David Pedri told reporters at a news conference.

"This is somebody who came to work that day hoping to go home to their family and they didn't," Pedri said about the guard. "We will do everything in our power ... to make sure an incident like this never occurs again."

During the altercation, the doors to the elevator shaft opened and the two fell down the shaft, WYOU-TV, the local CBS affiliate reported, citing police.

Pedri declined to answer questions about the nature of the altercation or how the guard and inmate died, WYOU-TV reported. Local authorities have launched an investigation into the incident.

(Reporting by Laila Kearney in New York and Brendan O'Brien in Milwaukee; Editing by Michael Perry and Bill Trott)