The state medical examiner's office has confirmed asphyxiation as the official cause of death of a part-time Census worker found dead at a Clay County cemetery, a spokeswoman said.

The office had listed asphyxiation as the cause of death earlier based on preliminary autopsy results.

William Sparkman, 51, was found Sept. 12 with a rope around his neck tied to a tree in southern Clay County.

State police are still trying to determine whether Sparkman died as a result of an accident, homicide or suicide.