GREENVILLE, Calif. (AP/CBS13) — California’s largest wildfire tore through the small Plumas County town of Greenville on Wednesday evening, destroying businesses and homes as the sky was cast in an orange glow.

Authorities were urging the town’s residents to evacuate south toward the Quincy area.

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“If you are still in the Greenville area, you are in imminent danger and you MUST leave now!!” the Plumas County Sheriff’s Office posted on Facebook earlier Wednesday.

 

The 3-week-old Dixie Fire has grown to over 428 square miles across Plumas and Butte counties.

Firefighters had been trying to protect the town of 800 by clearing debris from roads and marking hazards.

Pandora Valle, a spokesperson with the U.S. Forest Service, earlier told The San Francisco Chronicle that “firefighters are fighting for the town of Greenville,” but could not provide further details about the damage.

The destruction came amid a red flag warning issued by forecasters warning of hot, bone-dry conditions with winds up to 40 mph. That could drive flames through timber, brush and grass, especially along the northern and northeastern sides of the vast Dixie Fire.

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“I think we definitely have a few hard days ahead of us,” said Shannon Prather with the U.S. Forest Service.

Firefighters were able to save homes and hold large stretches of the blaze. But flames jumped perimeter lines in a few spots Tuesday, prompting additional evacuation orders for about 15,000 people east of Lake Almanor, fire officials said.

Heat from the flames created a pyrocumulus cloud, a massive column of smoke that rose 30,000 feet in the air, said Mike Wink, a state fire operations section chief.

Dawn Garofalo watched the cloud grow from the west side of the lake, where she fled with a dog and two horses, from a friend’s property near Greenville.

“There’s only one way in and one way out. I didn’t want to be stuck up there if the fire came through,” Garofalo said.

From her campsite on the lake bed, she watched the fire glowing on the horizon before dawn. “The flames were huge. They must have been 500 feet high. Scary,” she said.

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The fire has threatened thousands of homes and destroyed 67 houses and other buildings since breaking out July 14. It was 35% contained.