GRESHAM, Ore. -- A 39-year-old Eugene man was found dead Monday morning along a trail near Mount Hood Community College, and an autopsy could find no obvious cause of death.

The body of Michael Charles Porter, 39, of Eugene, Ore., was found along the trail to Beaver Creek near the community college campus Monday morning shortly before 11. Authorities in Gresham, Ore., do not know why Porter was in the area.

An autopsy failed to determine a cause of death. Exposure to the elements is believed to have been a contributing factor to his death, according to Gresham police.

Investigators do not suspect foul play. A final determination regarding cause of death is pending toxicology reports.