It was like a scene from a horror film: A 27-year-old man plummeted into a gaping hole that suddenly opened beneath a house, trapping him beneath foundation rubble and killing him.

Authorities say the home, built in the 1980s, may have been sitting atop a decades-old underground mine. Recent rains could have softened the ground under the home, in an isolated area near Lake Alta.

"It's unbelievable," Placer County Sheriff's Department spokeswoman Dena Erwin said. "From the front of the house, it's absolutely normal. Then, in the middle of the house, is this enormous hole."

The victim was awake and on the ground floor about 9:30 p.m. Friday when the concrete foundation near the kitchen gave way, sending him plunging into to the ground, Erwin said.

Rescuers had trouble reaching him because the ground began to shift, creating an unsafe situation for work crews. Authorities returned to the home Sunday to try and remove the man's body, though geologists were still testing the house's soundness.

The man's identity hadn't been positively established.