Scores of homes perched on a cliff overlooking the Pacific Ocean in LA County have had their electricity shut off amid steadily worsening landslides.

The community of Rancho Palos Verdes - 25 miles (40km) south of downtown Los Angeles - has long grappled with unstable land, but authorities say the problem has worsened in recent months.

Now, utility companies are stepping in, fearing fires and other destruction caused by rapidly shifting land while some residents insist on staying in their multi-million dollar homes.

The decision by power utility company Southern California Edison on Sunday cut electricity to 140 homes in the neighbourhood of Portuguese Bend, with further cuts possible.