More than 20 missing following mudslide

That is down from the 30 people they previously considered missing in Washington state.

The Snohomish County medical examiner’s office said it has positively identified 18 of the 24 victims in the official death toll.

Snohomish County executive director Gary Haakenson says the remains of three additional victims were found on Monday, but they have not yet been included in the medical examiner’s official numbers.

The slide struck a rural area north-east of Seattle on March 22.

Steve Harris, a division supervisor for the search effort, said search teams are learning more about the force of the mudslide, and that is helping them better locate victims in a debris field that is 70 feet deep in places.

“There’s a tremendous amount of force and energy behind this,” Mr Harris said of the slide.

He said search dogs were the primary tool for finding remains in the small, mountainside community about 55 miles from Seattle. He said searchers were finding human remains four to six times per day.

A makeshift road completed over the weekend links one side of the 300-acre debris field to the other.

Searchers face treacherous conditions, including household chemicals, septic tanks, gasoline and propane containers. When rescuers and dogs leave the site, they are hosed off by hazardous materials crews.

Governor Jay Inslee yesterday asked President Barack Obama for a major disaster declaration in Snohomish County to make programmes available to help individuals, households and businesses.