“The movement has accelerated dramatically over the last 12 months, where some areas are moving up to 10 inches (25cm) a week,” said city council member David Bradley, according to CNN.

“You can almost see the ground move.”

An additional 105 customers in the city of 42,000 people were notified that they would lose power on Monday.

Last week, a downed powerline sparked a small wildfire in Portuguese Bend.

“The land movement in the Portuguese Bend community has created such a dangerous situation that we have made the very difficult decision to disconnect power indefinitely to prevent that equipment from igniting wildfire,” Larry Chung, a spokesman for the power company.

Gas and water has already been disconnected in the upscale neighbourhood.

The 680-acre (276-hectare) landslide has been ongoing for years at a slow pace. But it has accelerated in part due to heavy rainfall in California over the past two years, expert say.

“The acceleration that’s happening currently is beyond what any of us could have foretold, and it demands more response from the state, more response from the federal government,” said Los Angeles County Supervisor Janice Hahn at a news conference on Sunday.

The top county official added that $5m (£3.8m) had been set aside for disaster relief, but more was needed. She called on California Governor Gavin Newsom to personally visit the area and declare a state of emergency.