FORT TEJON (CBS SF) — A massive mudslide and flash flood has forced the shutdown of the Grapevine on Interstate 5 in both directions near Castaic.

Traffic was being diverted but hundreds of drivers were stranded, trapped by rocks, mud and debris that flowed onto the highway.

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The flooding began during the afternoon commute.

According to KCAL 9 “at least 6 cars were swallowed up by mud.”

The CHP said the highway will be closed from the Lancaster Freeway to Fort Tejon for at least 10 hours.

The stretch of highway north of Los Angeles known as The Grapevine is a major connector between Central and Southern California.

Torrential rains the last several hours have caused flash floods near Lake Hughes, according to the National Weather Service. There were also reports of a funnel cloud in the area.

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The Los Angeles County Fire Department rescued 4 stranded drivers and 2 dogs, and were checking cars buried in the mud for more victims.

Caltrans tweeted a warning for drivers to avoid the area, and said emergency vehicles were arriving.

The National Weather Service issued a flash flood warning for San Luis Obispo County and the interior valleys. Thunderstorms and heavy rains were reported throughout the affected area, with as much as 2 inches of rain per hour.

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