A landslide tore apart luxury homes on Monday in the Palos Verdes Peninsula, Southern California, leaving a confused pile of collapsed roofs, shattered walls, tilted chimneys, and decks hanging over an adjacent canyon. The landslide occurred in the city of Rolling Hills Estates, Los Angeles County, starting on Saturday when cracks began to appear in structures and the ground. Twelve homes were marked with red tags as unsafe, and residents were given only 20 minutes to evacuate.

The destruction escalated over the weekend and continued into Monday.

Neighbors and residents in the area report that the landslide is rapidly progressing, with audible cracking sounds coming from the shifting houses.

Initially, it was believed that all the homes marked with red tags were sliding, but Assistant City Manager Alexa Davis clarified on Monday afternoon that 10 were actively moving. Sixteen others were being monitored but did not require evacuation, Davis said in an email.

Residents believe that the initial problem was caused by heavy rains last year and the resulting underground water. However, the exact cause of the landslide is still unknown.

Many of the displaced residents were uncertain if they were insured for such losses, including someone who moved in two months ago after completing the real estate transaction. The county assessor was scheduled to meet with the residents to inform them that they could apply for property tax waivers. "We gave them 20 minutes on Saturday night to evacuate and gather their belongings. Obviously, they couldn't take everything," said Janice Hahn, Chair of the Los Angeles County Board of Supervisors, who represents the area.

Destructive landslides have occurred previously in the Palos Verdes Peninsula, which rises above the Pacific Ocean on the county's south coast, offering residents spectacular views of the ocean and greater Los Angeles.

A landslide that began in 1956 destroyed 140 homes in the Portuguese Bend area of the city of Rancho Palos Verdes, and the ground continues to move there. The slide coincided with the construction of a road through the area, which is situated on top of an ancient landslide.

Among other notable earth movements on the peninsula, a 2011 slide severed the blufftop ocean road near White Point in the San Pedro section of Los Angeles several months after engineers began noticing cracks and cordoned off the area for study.

According to an overview by the U.S. Geological Survey in conjunction with the California Geological Survey, the complex landscapes of Southern California contribute to landslides.

Some of the many potential factors include earthquakes, steep slopes, sedimentary soil that is not rock hard, and water percolating down into the earth after heavy rains, the report states.

Human-induced landslide factors include construction without proper grading of slopes, alteration of drainage patterns, and disturbances of old landslides. This news report is distributed by the website www.ozarksfirst.com.