Crews are tearing down a multimillion-dollar San Francisco house that is sliding off a hill, threatening other homes.

Homeowner Ronald Martell says the house has separated more than a foot from the curb and has sunk more than a foot.

The city ordered an emergency demolition Thursday, and work continued Friday. The city has also ordered other nearby home owners to prove their houses are safe.

What's causing soil to shift under the house is unclear, although it could be related to El Nino storms that have drenched the San Francisco Bay Area.

The family bought the three-story, mid-century home for $2 million in October but had not moved in pending a remodel.

Martell says the family would love to rebuild but that will depend on what's causing the slide.