NEW HARMONY, Utah - A wildfire that burned three homes in southwestern Utah over the weekend blackened 2,000 more acres on Monday in hot, windy conditions. The Mill Flat fire has burned about 15 square miles and is considered 5 percent contained, fire officials said late Monday afternoon. Stiff winds pushed the fire to the northeast as additional crews battled it from the air and on the ground, said Jennifer Sullivan, a spokeswoman for the crew fighting the fire. "The winds are just terrible," Sullivan said. "Hopefully tomorrow with the winds a little bit calmer, they'll be able to get closer to it." Meanwhile residents began returning to their homes Monday morning after authorities lifted an evacuation advisory for hundreds of homes in the area.

Residents however remain on a one-hour notice to leave again if the fire picks up.

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The lightning-caused fire had been burning in the remote Pine Valley wilderness area for more than a month before it flared up over the weekend, forcing hundreds from their homes and prompting new criticism that fire officials didn't attempt to extinguish it immediately after it started.

Bevan Killpack, a district ranger for the Dixie National Forest, said he had hoped the fire would play its natural role in helping clear out thick underbrush and dead conifers that impede wildlife movements and growth of aspen.

The buildup also posed a risk for a large-scale, landscape-clearing blaze and flooding in the aftermath -- a situation the burn this summer was intended to alleviate, Killpack said.

The blaze grew slowly over the month, scorching about 1.6 square miles, and the plan appeared to be working until the fire expanded rapidly Saturday afternoon with the help of unexpectedly heavy winds, he said. The fire raced down two canyons and a collapsed smoke column made it difficult for crews to fight it.

"It just went to hell," he said.

A national incident team took over management of the fire early Monday morning. There are about 650 people assigned to the fire along with four helicopters, 30 engines and two bulldozers.

Utah Gov. Gary Herbert flew over the fire in a helicopter Sunday afternoon and, later in the day, echoed concerns from some locals about why the fire was initially allowed to burn in the area that's been designated as wilderness since 1985.

About 150 people were told to leave and, at one point, fire officials said the blaze threatened 550 homes and 58 commercial buildings. Aside from the three homes that burned, eight other outbuildings were also destroyed.

Killpack, the forest ranger, said a scientific team will be on the scene later in the week to begin assessing the possibility of erosion and spring floods in the wake of the fire.

FOX 13's Ben Winslow reports.

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