Authorities searching for victims of the March 22 mudslide in the state of Washington said Monday that the death toll had risen to 33, with the list of missing people dropping to a dozen.

A rain-soaked hillside collapsed near the small town of Oso in Snohomish County, about 60 miles north of Seattle. Of the 33 people confirmed dead, 30 have been identified, the Snohomish County medical examiner's office said, in a statement. The massive mudslide was at least 135 feet wide and 180 feet deep in size. Officials have said that it destroyed a neighborhood of about 30 homes, blocked State Route 530, and jammed the north fork of the Stillaguamish River.

“The mudslide is an enormous tragedy, but the efforts by the first responders is an inspirational American story,” Jeh Johnson, homeland security secretary, reportedly said in a statement. “The Department of Homeland Security, FEMA and the entire federal government is here to support the governor and his team.”

Recovery crews are reportedly still searching for another 12 people, including three children -- a 2-year-old girl and two boys, aged four and 14 -- who remained unaccounted for as of Monday morning. Nearly 900 search crew members, including 350 National Guard soldiers, have sifted through tons of mud and crushed houses to aid in the recovery over the past several days.

President Barack Obama declared the landslide a federal emergency last week, which helped provide the local and state governments with federal resources and teams to respond better to the disaster.