An inmate at an east Arkansas prison serving multiple life sentences for raping and assaulting Boy Scouts as a troop leader in the 1990s has died.

A spokesperson for the Arkansas Department of Corrections told KNWA/FOX24 that Charles “Jack” Walls, 75, died of natural causes on Aug. 23 at the East Arkansas Regional Unit in Brickeys.

Walls was given three life sentences and two 40-year sentences, to be served consecutively, for six counts of rape in Lonoke County, according to court documents.

Court records said that Walls was a Boy Scouts troop leader who sexually assaulted boys under his care.

At a hearing in the case, it was revealed that Walls introduced his victims to weapons, alcohol, pornography and sexual acts with him.

The abuse occurred between 1991 and 1993, court documents say. Walls was sentenced on Aug. 21, 1998.