A giant sinkhole in Lake County near San Francisco has begun the slow process of swallowing up homes.
Eight homes in the subdivision 100 miles north of San Francisco have been evacuated, while 10 others are on notice for potential imminent evacuations, the Los Angeles Times reported.
Mail deliveries to the area, called Lakeside Heights, have been stopped as a precaution as well.
It is possible that all 30 of the neighborhood's homes will have to be abandoned if the sinking cannot be stopped.
"It's a slow-motion disaster," said Randall Fitzgerald, a writer who bought his home there a year ago.
The Lake County division, which was built 30 years ago, usually faces groundwater shortages. But officials believe that water bubbling to the surface all of the sudden may be a factor in the slow sinking, though they are not sure why.
"That's the big question," Scott De Leon, the county's public works director, told NBC News. "We have a dormant volcano, and I'm certain a lot of things that happen here (in Lake County) are a result of that, but we don't know about this."
Unlike Florida's sinkholes, which often appear rapidly, this natural disaster in Northern California's hilly volcanic terrain is moving slowly and unpredictably.
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