SIOUX FALLS, S.D. (AP) — A Sioux Falls eye doctor spent Sunday surveying earthquake damage at a winery he co-owns in California's Napa Valley.

Vance Thompson tells the Argus Leader that the epicenter of the powerful Sunday earthquake that struck the heart of California's wine country was close to a production facility for Jessup Cellars, which he owns with other partners including Sanford Health executive Dan Blue.

Thompson says facility workers are fine but shook up. Some have damaged homes.

Jessup Cellars has tasting rooms in Yountville and St. Helena in California that appear to be structurally sound.

The magnitude 6.0 earthquake struck at 3:20 a.m. local time Sunday near the city of Napa. The quake injured scores of people, knocked out power to thousands, ruptured gas and water lines and sparked fires.

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