By Dan Wing

WILKES-BARRE, Pa. (CBS/AP) — A guard and an inmate are dead after an incident at Luzerne County Prison in Wilkes-Barre, PA.

Luzerne County officials did not release details of the incident, but say the guard and a 27-year-old inmate died following a brief altercation Monday night.

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On Tuesday, authorities identified the officer as 25-year-old Kristopher Moules of Larksville.

Officials previously identified the inmate as 27-year-old Timothy D. Gilliam Jr.

William Lisman of the Luzerne County Coroner says both men died of multiple traumatic injuries from a fall. The inmate’s death was ruled accidental. Lisman is not yet ruling on the officer’s death, pending further investigation.

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The prison was placed on lockdown for a short time, but officials say this was an isolated event.

Officials aren’t yet saying what led to the altercation or how exactly the two men died.

The Luzerne County District Attorney’s Office and Pennsylvania State Police are investigating.

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