NEW HARMONY, Utah - Fire crews say hot and windy conditions could fan a wildfire that has already blackened more than 15 square miles, destroyed homes and prompted evacuations in a small, southwestern Utah town. The lightning-sparked Mill Flat fire had been burning in the Pine Valley Wilderness area for more than a month before it flared up over the weekend near the town of New Harmony.

Kenton Call, spokesman for the Dixie National Forest, said some houses were lost but didn't have an exact count Sunday morning. "Between 100 and 150 people were forced out of their homes on Saturday," he said. On Sunday morning, members of Washington County Search and Rescue were going door-to-door urging more residents to leave the area.

The Federal Emergency Management Agency announced early Sunday that it would contribute to firefighting costs after the state confirmed more than 6 square miles had burned. FEMA said the fire was threatening 550 homes and 58 commercial properties. Firefighters continued to battle the fire into the evening Saturday with air tankers dropping retardant to slow the blaze. They braced for more dangerous conditions Sunday with hot, dry and windy weather expected.

Crews are focusing on defending buildings and other property, Call said. The blaze is also actively burning west and north of town. "Today's challenge for our firefighters is to provide structure protection in the face of red flag warnings," incident commander Randy Turrill, said in a statement Sunday. "Public and firefighter safety is our top priority." Heavy smoke and ash from the fire has been dispersed throughout southwestern Utah, fire officials said.

More crews were scheduled to arrive at the fire later Sunday, including a national incident team. Call said he expects that crew to take over fire management Monday morning.

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