A slow-motion disaster continued unfolding in the Wyoming resort town of Jackson on Saturday, as a creeping landslide that split a hillside home threatened to swallow up more houses and businesses.
The ground beneath the 100-foot hillside had been slowly giving way for almost two weeks before the downward movement accelerated in recent days.
With rocks and dirt tumbling down, officials suspended efforts to shore up the slope and said they were uncertain what else could be done.
"When is it going to go? How long is it going to last? These are the questions we just can't answer and they're what everyone wants to know," town spokeswoman Charlotte Reynolds said.
Authorities said there could be a variety of causes for the slide, including prior construction at the site, warmer weather and a wet winter that put more water into the ground where it acts as a lubricant for unstable rocks and soil.
Experts say the hillside is unlikely to suddenly collapse like the March 22 landslide in Oso, Wash., that killed 39 people. More likely, large blocks of earth would tumble down piece by piece.
But the threat is real and authorities are enforcing an evacuation order in hopes of avoiding injuries. Town officials first noticed significant hill movement April 4. They evacuated 42 homes and apartment units April 9.
By Saturday morning, the shifting earth had bulged a road and a parking lot at the foot of the hill by as much as 10 feet.
Jackson resident Rick Johnson lives less than a quarter-mile from the slide area. He said a retaining wall on his property has been shifting in recent years, but he had not given it too much thought until the slide started just down the road.
As he watched workers at the top of the slide area taking measurements of the previous night's movements, Johnson said he had no doubt that the natural geologic forces at work were amplified by the construction at the foot of the mountain.
"I think they are just messing with Mother Nature and they didn't think of the long-term consequences," he said.