NAPA COUNTY (CBS SF) — One person has died in a mudslide on Highway 121 in unincorporated Napa County Tuesday evening, according to the California Highway Patrol.

The incident was reported at just after 5 p.m. near State Highway 121, also known as Monticello Road, and Wild Horse Valley Road.

Napa CHP confirmed that the crash was caused by a mudslide on the highway and that one vehicle was involved and that one person had died.

The vehicle was hit by a rock from the hillside and then hit by the mudslide, according to Napa CHP.

CHP officials said the mudslide was not stable enough for them to try to remove the driver and the vehicle Tuesday night.

Authorities said that the highway would be closed until at least daylight on Wednesday. Caltrans engineers will check out the hillside on Wednesday morning.

A Sig-alert has been issued, closing Highway 121 in both directions between Vichy Avenue and Wooden Valley Road, according to the CHP.

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