Rockville Mayor Dan McGuire said the house was completely buried under dirt and large boulders, with wood and parts of the house visible in the rubble, the Salt Lake Tribune reported Friday.
"It just flattened it," McGuire said of the slide.
Kurt Wright, police chief of Springdale and Zion Canyon, said two bodies had been found in the rock slide. The boulders that fell on the home weighed several hundred tons, he said, and probably killed the victims instantly.
A boulder will have to be moved to get to the bodies, he said, and crews were evaluating how that could be done.
Wright described the boulder as "larger than the house and it was two-story house," the Deseret News reported.
"Our concern is finding something big enough to move the boulder," Wright said.
The rock fall was probably caused by unusually low temperatures and heavy snowfall, Wright said. Warmer temperatures Thursday may have loosened the frozen rocks and caused them to roll down the hill.
He said the boulder traveled about a quarter mile down the mountain before landing on the house, the Deseret News reported. A second large boulder landed in the yard.
Nearby residents were asked to evacuate because of the risk of a second slide, but they were back in their homes Thursday evening.
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