Construction workers rebuilding a bridge in the San Francisco Bay Area on Friday unexpectedly found two people living in a cave dug into an embankment, authorities said.
Crews were excavating at the site of the old bridge in Vallejo when they heard voices and switched off their digging equipment, Tom Walker, the project manager for the city, told the San Francisco Chronicle.
They discovered a cave about 6m by 0.9m high in the side of the embankment.
"We called in the police and fire departments to make sure we didn't injure anyone" in relocating the occupants, Walker said. "It's a rescue operation."