BRECKENRIDGE, Colo. (AP) — A 71-year-old man from north suburban Northbrook was pronounced dead after he was found unconscious on a run at Breckenridge Ski Resort.

The Summit Daily reports William Hass was found unconscious on a run Monday afternoon. It does not appear that he crashed into anything while skiing, and Summit County Coroner Regan Wood says Hass died of natural causes.

Hass’ death was the fourth on the ski slopes in Summit County this season, and the third that involved a medical problem. Along with the four deaths in Summit County, there have been at least three other skiing or snowboarding fatalities in Colorado this season.

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