The luxury Santa Barbara district of California - home to celebrities including Oprah - was hit by "waist-deep mud" in the early hours of Tuesday morning after a huge river of mud cascaded downhill following heavy rains.
A third day of searching for survivors has resumed with about 700 emergency workers expected to recover more bodies.
The horrific catastrophe has so far left 17 people dead and 43 missing. Some of these might be out of communication range, said Santa Barbara County Sheriff Bill Brown at a Thursday briefing.
He said: "Realistically we suspect we are going to have the discovery of more people killed in this incident."
GETTY/BING/EXPRESSCalifornia mudslide map: Where is Oprah Winfrey's home in Santa Barbara?
Oprah - who is currently being back for a future presidency bid by several A-list celebrities - previously offered up prayers for the mudslide's victims.
She also posted videos on Instagram from outside her Montecito home as she waded through deep mud in her yard and watched a rescue helicopter fly overhead.
The TV host wroteon Tuesday: ”What a day! Praying for our community again in Santa Barbara... Helicopters rescuing my neighbors. Looking for missing persons. 13 lives lost."
Thousands of people were ordered to evacuate the area, which was ravaged by Thomas Fire wildfire in California in the USA in December, as the floods swept downstream.
The mud deluge has covered residential blocks and Highway 101, a major north-south route along the coast.
Where is Oprah Winfrey’s house in Santa Barbara?
The TV talk host legend’s grand house in Montecito, California, is reported to be worth $28 million.
It is the wealthiest district in Santa Barbara County, home to A-list celebrities and a population of 8,965, according to the 2010 census.
Positioned next to the coast on the North Pacific Ocean, it occupies the lower foothills of the Santa Ynez Mountains and enjoys a cool mediterranean climate all year round.
Google MapsOprah Winfrey’s Montecito house can be viewed from Google Maps
Oprah’s house, nicknamed “The Promised Land”, is located on a 42-acre site in Montecito with mountain and ocean views, says satellite imagery website virtualglobetrotting.com.
Varsity also reported that Oprah purchased a further $28.85 million to buy horse ranch Seamair Farm in February 2016. The 23.26 acre equestrian estate borders her current home.
Which other celebrities live in Montecito?
Ellen DeGeneres, host of the The Ellen DeGeneres Show, and actor Rob Lowe are other famous residents of Montecito.
Other famous people who live in the area include Al Gore, Patrick Stewart, Jane Seymour and Malcolm McDowell.
Ellen has reportedly bought a property next door to Oprah’s, entertainment website TMZ reported last month.
TMZ said: “Ellen's new spread put her back just under $7.2 mil and sits on nearly 6 acres and includes 2 Spanish style homes -- one is 3,000 sq. ft and was built in 1845.
"The other is 3,600 sq. ft. ... built in 2006. There's also a barn for horses -- and the place has amazing ocean views.
Google MapsMontecito map: People were trapped at the Birnam Wood Golf Club
“It's in a gated community right next to Oprah. Ellen can literally go knock on her door for a cup of sugar.”
The comedian took to Twitter after the mudslide to post a picture of the damage caused.
She wrote: “This is not a river. This is the 101 freeway in my neighborhood right now. Montecito needs your love and support.”
Actor Rob Lowe, who starred in political drama The West Wing, is one celebrity who lives in Montecito.
He tweeted: “Mourning the dead in our little town tonight. Praying for the survivors and preparing for whatever may come. #Montecito”