(Adds updated death toll)
By Alex Dobuzinskis
MONTECITO, Calif., Jan 12 (Reuters) - Rescue crews expanded their search on Friday for five missing people as the death toll rose to 18 from mudslides in Southern California that damaged hundreds of buildings and caked highways with sludge.
About 1,250 emergency workers raced against the clock to find survivors with drones, heavy equipment and sniffer dogs in the rescue and clean-up efforts, the California Governor's Office of Emergency Services said.
The latest victim, 87-year-old Joseph Bleckel, was found in his Montecito home on Friday, Santa Barbara County Sheriff Bill Brown said, adding that the remaining missing were between the ages of 2 and 30.
"We've got a window that's closing, but we're still very optimistic. There's been plenty of cases where they've found people a week after," Santa Barbara County Fire Department spokesman Mike Eliason said earlier on a muddy Montecito street especially hard-hit by the mudslide.
Officials said secondary searches of damaged structures were under way.
The number of missing has fluctuated as people were located, said the Santa Barbara Sheriff's Office. Authorities said on Thursday night that 43 people were unaccounted for.
Residents in some areas were subject to a new mandatory evacuation on Friday, emergency officials said, adding the unstable environment remained a threat.
Triggered by heavy rains, the massive slides struck before dawn on Tuesday. Walls of mud and debris cascaded down hillsides stripped of trees and shrubs by last month's wildfires, including the Thomas Fire, the largest blaze in the state's history.
Excavators carrying rescuers in their buckets plowed through mud-coated roads in search of the missing after some areas were buried in as much as 15 feet (4.6 m) of mud, emergency officials said.
"It is heavy. It's wet. It just exhausts the crews out there," Sacramento Fire Department Captain Pat Costamagna said in a social media video from the governor's emergency management office.
County officials have already ordered residents in most of the southeastern corner of Montecito, an unincorporated community east of the city of Santa Barbara, to leave their homes for what they said was likely to be one or two weeks to aid the search and recovery efforts.
In one of the worst-hit areas of Montecito, mud blew through doors and windows, filling the interiors of houses with muck and debris. The walls at one end of a home had disappeared, leaving its roof hanging precariously.
Downed power lines wrapped around trees at one property, while elsewhere the lines dropped almost to the ground. Elsewhere, cars were perched on mounds of earth and garage doors had caved in.
The area, northwest of Los Angeles, is home to many celebrities and other wealthy Californians who relish the seclusion and relative proximity to the city.
The cause of death for most of the victims will be listed as multiple traumatic injuries resulting from flash floods with mudslides, the Santa Barbara Sheriff's office said Thursday. The dead ranged in age from 3 to 89.
One of California's most celebrated roads, coastal Highway 101, was closed in parts of Santa Barbara County where mud was 2 feet deep in parts.
Residents of the mudslide-hit area were assessing their damaged homes, with some grateful their properties had survived.
"We have a yard to redo and hopefully our insurance will help out with that, but the people across from me, newer homes, gone," said Garrett Speirs, a 54-year-old artist who has been living in Montecito for 20 years.
"Everybody down below gone, two girls gone," Speirs said. "Two sixth-graders in the school our kids went to."
(Additional reporting by Keith Coffman in Denver, Chris Kenning in Chicago, Gina Cherelus and Peter Szekely in New York and Jon Herskovitz in Austin, Texas; Writing by Scott Malone and Jon Herskovitz; editing by Jeffrey Benkoe, James Dalgleish and G Crosse)
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