(Bloomberg) -- The wildfire that erupted in California’s Wine Country minutes after a PG&E Corp. power line went down has triggered a historic evacuation with state and county emergency responders calling on tens of thousands of people to flee their homes by Saturday afternoon.

‘Significant’ portions of Sonoma County were told to evacuate quickly before PG&E carries out a blackout that will plunge millions into darkness to prevent more wildfires from breaking out. Sonoma County Sheriff Mark Essick said at a media briefing Saturday that the evacuations are the largest he’s seen in the more than two decades that he’s been with the sheriff’s office -- even more extensive than the ones triggered by the devastating 2017 Wine Country fires.

The bankrupt California utility giant PG&E had an equipment failure on a high-voltage transmission line just before the fire broke out in the area late Wednesday. It started even as the company takes extreme measures to prevent blazes. The company is preparing to cut power to an estimated 2.5 million Californians on Saturday amid high winds in what would be the state’s largest deliberate blackout ever.

As of Saturday morning, the Kincade fire had scorched more than 25,000 acres of land and was threatening 23,500 structures, according to the state fire department.

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To contact the reporter on this story: Lynn Doan in San Francisco at ldoan6@bloomberg.net

To contact the editors responsible for this story: Sebastian Tong at stong41@bloomberg.net, Lynn Doan, Matthew G. Miller

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