DARRINGTON, Wash. -- Weary rescuers pressed through rain and their own exhaustion Thursday, searching for more bodies and a perhaps a miracle atop the pile of filth and debris that laid waste to a Washington town and killed at least 25 people.
Rescue and cadaver dogs occasionally led crews to a wrecked car or the ruins of a house containing a body. Teams then began removing the corpse, ignoring the muck that clogged their tools. As the victim was taken away, silence fell over the site.
The main goal now is to find more bodies and winnow the list of the 90 people who are missing in the mudslide that buried the community of Oso on Saturday.
But that doesn't prevent the more than 200 people working on the sludgy heap from clinging to hope that at least one survivor is waiting for them in some pocket of the pile, which is a square mile wide and 40 feet deep in places.
"My heart is telling me I'm not giving up yet," Snohomish County District 21 Fire Chief Travis Hots said. "If we find just one more person alive, it's all worth it to me."
After six days of searching, people are not the only ones showing signs of strain. Shane Barco's 3-year-old German shepherd has found bodies and body parts. But, Barco said, the dog gets frustrated when they don't find anybody alive.
Days of combing through what Barco called a blender of debris has exhausted the dog, leading Barco to stop the search for a while.
Authorities warned the community to expect a substantial rise in the death toll within the next two days as the Snohomish County Medical Examiner's Office catches up with the recovery effort.
Sixteen bodies have been recovered, but officials say at least nine more had been found as of Wednesday night. The medical examiner's office has so far formally identified only a single victim, 45-year-old Christina Jefferds. Family members have confirmed a handful of other fatalities to news organizations.
Five people injured by the mudslide remain in a Seattle hospital, including a 5-month-old boy in critical condition.
Besides the 90 missing, authorities are checking into 35 other people who may or may not have been in the area at the time of the slide.
If dozens more bodies are found or left entombed in the debris, the Oso mudslide could become one of Washington state's largest disasters. The 1980 eruption of Mount St. Helens killed 57 people, and a 1910 avalanche near Stevens Pass that struck two trains killed 96.
"We do know this could end up being the largest mass loss of Washingtonians," Gov. Jay Inslee said Thursday. "We're looking for miracles to occur."
The searchers walk on plywood pathways to keep from sinking into the sucking slurry. Their task was made more difficult Thursday by the rain that saturated the sand, silt and clay that make up the debris pile. The moisture made the already treacherous surface even more unstable and raised concern about the safety of collapsed hillside above them.
"Right now there (is) no risk of additional slides, but we're watching the rain," said Steven Thomsen, the county's public works director. "If it starts to move, we'll pull the crews out, but we don't see that happening."
A University of Washington researcher now says there were two major slides on Saturday morning.
The bigger slide that hit Oso lasted more than 2 minutes, and was followed four minutes later by the second one, wrote Kate Allstadt on the Pacific Northwest Seismic Network blog.
Seismic signals also recorded more than a dozen smaller slides that continued for more than an hour.
"The big pulse was the main volume of material that broke down from the slope and tumbled down toward that valley," said Bill Steele, the seismology lab coordinator and spokesman for the seismic network. "Another big pulse followed that, breaking loose another section of unstable slope."
The seismic signals showed that the slide was not triggered by an earthquake, Allstadt said.
Volz reported from Seattle.
Associated Press writers Rachel La Corte in Olympia, Wash., and Doug Esser in Seattle contributed to this report.
By MANUEL VALDES AND MATT VOLZ