WALNUT CREEK (CBS SF) — Firefighters are battling a three-acre vegetation fire Tuesday afternoon in Walnut Creek near the Lime Ridge Open Space, a Cal Fire spokesman said.

Fire crews responded shortly before 12:30 p.m. to a report of a grass fire in the 3800 block of Valley Vista Road, Contra Costa County Fire Protection District inspector Steve Aubert said.

As of around 2 p.m., the fire had consumed three acres and was 10 percent contained, Cal Fire spokesman Brandon Leitzke said.

No structures are being threatened and no injuries have been reported, he said.

Roughly 50 firefighters are working to douse the flames, Leitzke said.

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