A man has been convicted in the kidnap and slaying almost a decade ago of a co-worker whose bones were found buried in his eastern Pennsylvania yard.

A Monroe County judge on Friday convicted 55-year-old Michael Horvath of criminal homicide, kidnapping, evidence-tampering and abuse of a corpse in the 2013 killing of 41-year-old Holly Grim.

He was acquitted of an obstruction count.

Grim was last seen in Lehigh County’s Lower Macungie Township in November 2013.

She and Horvath had worked together at a company that makes church organs, authorities said. Horvath’s attorney called the case circumstantial.

Sentencing is scheduled Sept. 8.