A fast-moving wildfire charged down a mountainside onto a field, and a man and his father who were working there told the man's 11-year-old son to run.

Duane Houston escaped the fire on the edge of the Uinta National Forest but his father, 43-year-old Tracy Houston, and his grandfather, 63-year-old George Houston, were killed by the flames, authorities said. The owner of the field, 75-year-old Roger Roberson, died at a Salt Lake City hospital, officials said Saturday.

The fire started Friday morning north of Neola, about 100 miles east of Salt Lake City, and by Saturday afternoon it had charred about 23 square miles in the northeastern corner of the state.

Officials said crews had not begun to contain it and more hot, windy weather was forecast for Sunday. At nearby Vernal, there was little wind Sunday morning but humidity was only 22 percent, the National Weather Service said.

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The Houstons had gone to buy hay from Roberson, and were helping him move irrigation sprayers on his field in an attempt to block the flames.

Duane said he was told to run for their truck as flames and smoke filled the air.

"I ran and couldn't find the truck, so I kept running through trees, climbed two fences and followed the road," he told The Salt Lake Tribune.

He was treated at a hospital and released.

The town of Whiterocks and the nearby small community of Farm Creek were evacuated, the newspaper said. Uintah County Sheriff Jeff Merrell said buildings had been destroyed but he did not have a count.

Edson Gardner, of Fort Duchesne, went to Farm Creek to evacuate his mother, whose home was burned to the ground.

"It came down the canyon like a herd of horses," he said of the blaze. "The sheriff told us we had five minutes to get out."

Gov. Jon Huntsman requested aid from the Federal Emergency Management Agency.

In California, evacuees returned to their burned-out streets Saturday south of Lake Tahoe, where a wildfire had destroyed more than 200 homes and charred 3,100 acres, displacing about 3,500 people. Investigators said the blaze was started by an illegal campfire and was 80 percent contained.

Fire crews north of Los Angeles had a 19-square-mile blaze 80 percent contained, state fire department spokesman Rick Espino said Saturday. Four crew members had been injured battling the blaze that destroyed 12 homes and six buildings since it broke out a week ago in steep canyons south of the San Joaquin Valley, officials said.

In Montana, a nearly 6-square-mile blaze near Yellowstone National Park was 60 percent contained Saturday, officials said. Evacuation orders remained in effect for 45 to 50 summer homes.

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