Preliminary findings of an autopsy offer no answers as to what killed an 18-year-old resident at the Decker Lake Youth Center.

The medical examiner's office told Youth Corrections officials that Chris Walter's body didn't show any outward signs of trauma or any evidence of drug use. But until examiners run a toxicology test, they won't know for sure if the boy had drugs in his system when he died, said Department of Human Services spokesman Randy Riplinger.Walter had returned to Decker Lake, the juvenile equivalent of prison, just a day earlier on a parole violation.

Riplinger said Walter came to Utah on an interstate compact from California. While in Utah he committed new crimes, which led to him being imprisoned in Utah's juvenile secure facilities.

Officials are in the process of putting together a sociology report on the boy, who Riplinger said didn't appear to have an extensive criminal history. Some of his crimes were serious, though: armed robbery and aggravated assault, he said.

Walter recently starred in a play written by the inmates at Decker Lake, which portrayed gang life as a dead end. Officials said Walter had been placed in a trial program in Cedar City to help him sever his gang ties.