The highway closed east of Highway 43 for a couple of hours.
The California Highway Patrol said at least seven crashes had occurred, including one involving ten cars.
One crash resulted in moderate injuries and no one was injured in the other six crashes, officials said. No further information was immediately available. Officials say there was dense fog in the area.
FOG TRACKER: ABC30 Map showing Central California Fog Conditions
CHP officers from Fresno also responded to help authorities clear the scene. Officials warned drivers to travel carefully through the thick fog.
RELATED: Know the Road with the CHP: How can I stay safe in the fog?
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