CLAYTON (CBS SF) — A grass fire on Mount Diablo in Contra Costa County has grown to three acres Saturday night, with zero containment, Cal Fire reported.

UPDATE: Mitchell Fire on Mount Diablo Contained

Also, the Mitchell Fire – first reported at 5:18 p.m. as being along Mitchell Canyon Road at the city of Clayton’s south edge – is now being described as being off the Summit Road within Mount Diablo State Park, near the Juniper Campground not far from the top of the mountain, Cal Fire said.

Helicopters are leading the fire defense as of 6:30 p.m., as ground-based firefighting vehicles were still on their way to this difficult terrain.

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