It's been nearly a week since a mudslide swept the small town of Oso, Wash., leaving 17 dead -- an official count that authorities say will sharply rise over the next few days as they continue to search through the rubble for 90 people who are still missing.
Although local authorities said a 1.1 magnitude earthquake preceded the mudslide, officials from the U.S. Geological Survey on Thursday said it was not the cause. The Snohomish County landslide was mostly likely the result high rainfall and soil conditions that made the steep slope unstable -- a perfect recipe for the dramatic event.