Arlington, WA (CBS) - The search for survivors of a deadly Washington state mudslide grew Monday to include scores of people who are still unaccounted for, raising fears that the deep muck could have claimed many more lives than the eight bodies found so far.
In a race to find loved ones, family members and neighbors used chain saws and their bare hands to pick through wreckage that was tangled by the mud into piles of filthy debris.
At least two other bodies were found Monday, a responder told CBS affiliate KIRO-TV, bringing the unofficial death toll to 10. Authorities were expected to hold a news conference at 6:30 p.m. PT.
Authorities said they were looking for 108 people who had not been heard from since the disaster. They predicted that the number of missing would decline as more people are found to be safe. But the startling initial length of the list added to the anxieties two days after a mile-wide layer of soft earth crashed onto a cluster of homes at the bottom of a river valley.
"The situation is very grim," Snohomish County Fire District 21 Chief Travis Hots said, stressing that authorities are still in rescue mode and are holding out hope. But he noted: "We have not found anyone alive on this pile since Saturday."
About 30 houses were destroyed, and the debris blocked a mile-long stretch of state highway about 55 miles northeast of Seattle.
Adding to the worries was the timing of the mudslide, which struck Saturday morning, a time when most people are at home. Of the 49 structures in the neighborhood, authorities believe at least 25 were full-time residences.
More than a foot of rain has fallen here this month - twice as much as normal. The ground was saturated but we're told no official warning was issued, reports CBS News correspondent Danielle Nottingham.
"This came out of nowhere. No warning. They had very little time," said John Pennington, Snohomish County Emergency Management director. "It was considered very safe. Very candidly, I just don't think many people saw that this portion of the slide ... would come through."
Retired firefighter Gail Moffett, who lives in nearby Oso, said she knows about 25 people who are missing, including entire families with young children.
"It's safe to say I'll know everyone affected or who they are," Moffett said. "There's so much pain going on in the community right now."
Elaine Young and her neighbors uncovered several bodies Sunday and had to contact authorities to get them removed.
They also found a chocolate Labrador named Buddy alive, and helped pull the dog from the rubble, leading her to wonder if other survivors could be out there, desperate for help.
"If we found a dog alive yesterday afternoon that we cut out of a part of a house, doesn't that seem that maybe somebody could be stuck up under part of a house and be alive too?" asked Young, whose home survived the slide but was on the edge of the devastation.
She said she realized searchers need to stay safe, but lamented the pace of rescue efforts.
Authorities believe Saturday's slide was caused by recent heavy rains that made the terrain unstable.
From the beginning, rescue crews on the ground have faced dangerous and unpredictable conditions as they navigated quicksand-like mud and debris that was 15 feet deep in some places. Some who went in got caught up to their armpits in the thick, sticky sludge.
The threat of potential flash floods or another landslide also loomed over rescuers. On Monday, some crews had to pull back because of concern that a hillside could shift.
Pennington said the list of names of those who remain unaccounted for included construction workers who were working in the area and people just driving by. But, he cautioned, it does not necessarily mean there are scores of additional fatalities.
"It's a soft 108," Pennington said, explaining that the number would almost certainly fall as people are slowly located.
The spirits of search-and-rescue teams were raised late Saturday when they heard cries for help from the flotsam of trees, dirt and shattered wood. But no one else has been found alive.
On Sunday, crews were able to get to the soupy, tree-strewn area after geologists flew over in a helicopter and determined it was safe to search for survivors, Hots said.
They did not search the entire debris field, only drier, safer areas, he added.
The slide blocked the North Fork of the Stillaguamish River, which is continuing to back up, officials said. Authorities said Monday at least seven homes are now flooded, and more flooding is expected.
Frequent, heavy rain and steep geography make the area prone to landslides. Less than a decade ago, another slide hit in the same general area. Geologists and other experts said the river probably caused some erosion in the area that was carved by glaciers.
Washington Gov. Jay Inslee described the scene as "a square mile of total devastation" after flying over the disaster area Sunday. He assured families that everything was being done to find their missing loved ones.
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