LINCOLN - A Vermont man serving a sentence for the killing of a 10-year-old boy he met at a carnival in Cass County has died at the Tecumseh State Correctional Institution.

Lloyd Schoonmaker, 80, died Wednesday while serving a 10-year to life sentence for second degree murder. 

The corrections department says while a cause of death has not yet been determined, Schoonmaker was being treated for a medical condition.

A jury convicted Schoonmaker in the strangling death of 10-year-old Bobby Dooley 53 years ago.

Prosecutors say the boy and some friends worked briefly at a carnival under Schoonmaker’s supervision, but the boy did not return home. Schoonmaker was part of the search party and told the boy’s family that Dooley had planned to run away.

Following interrogation, Schoonmaker led authorities to where Dooley’s body was discovered near Plattsmouth.

Schoonmaker was deemed incompetent to stand trial from 1973 to 1981. He began his sentence on June 11, 1982.