Storms have triggered other catastrophic slides, including one that killed 150 people in Virginia in the wake of Hurricane Camille in 1969 and another that killed 129 when rain from Tropical Storm Isabel loosened tons of mud that buried the Puerto Rican community of Mameyes in 1985.
Rescuers, military personnel, volunteers and search dogs pressed on Friday, driven by the hope of finding at least one survivor. But the operation had changed, said Snohomish County fire battalion commander Steve Mason.
"It started with hasty searching," he said. Now "we want to be more methodical."
Crews that had worked for days in the rain and mud were getting some relief as replacements arrived. The Colorado National Guard sent 16 members of its fatality search-and-recovery team to Washington.
A new crew of volunteer diggers showed up in an Arlington school bus Friday and marched single file toward the debris pile.
"There are people down here digging for their loved ones," Mason said.
The county medical examiner's office has so far formally identified five victims: Christina Jefferds, 45, of Arlington; Stephen A. Neal, 55, of Darrington; Linda L. McPherson, 69, of Arlington; Kaylee B. Spillers, 5, of Arlington and William E. Welsh, 66, of Arlington.
The body of Jefferds' granddaughter, 4-month-old Sanoah Huestis, was found Thursday, said Dale Petersen, the girl's great-uncle.
Volz reported from Seattle.
Associated Press writers Manuel Valdes in Darrington, Phuong Le and Doug Esser in Seattle, and researchers Judith Ausuebel, Jennifer Farrar and Susan James contributed to this report.
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