An autopsy of a worker who was found dead on the job May 15 at the Sappi paper and pulp mill in Cloquet is complete. The Midwest Medical Examiner’s Office reports that Ryan Martin, 53, died of natural causes related to atherosclerotic heart disease.

Cloquet police and fire responders were called to the mill shortly before 5 p.m. May 15 and found Martin dead on the scene, prompting an investigation by the Occupational Safety and Health Administration and a referral of the case to the medical examiner.

Martin graduated from Morgan Park High School in 1982.