Media playback is unsupported on your device Media caption Rescue workers observed a moment of silence for the victims on Saturday

The number of people missing from last week's Washington state mudslide has been revised down substantially from 90 to 22, the authorities say.

The official death toll has risen to 24, with several bodies yet to be formally identified.

Rescue workers halted operations briefly on Saturday to observe a moment's silence for those who died.

It has been over a week since the town of Oso, north of Seattle, was struck by a 177ft (54m) wall of mud and debris.

Identification

The authorities say the number of those killed is believed to be at least 27 but that the official tally does not include those who have yet to be formally identified.

Jason Biermann, of the Snohomish Department of Emergency Management, said the crews were not always recovering complete remains, making it difficult to identify those killed.

"Often they are making partial recoveries," he said.

More than 200 rescue workers are involved in the rescue operation, which has been hampered by days of heavy rain.

They paused for a moment's silence at 10:37 (17:37 GMT) on Saturday, a week after the landslide struck.

"I know that every Washingtonian holds in their heart the people of the Stillaguamish Valley and we all wish we could ease their pain," said Washington governor Jay Inslee.

Image copyright Reuters Image caption Members of the Washington National Guard have joined civilian workers in the clear up operation

Image copyright AP Image caption Workers and volunteers observed a moment of silence on Saturday

Snohomish County executive director Gary Haakenson told reporters on Friday it was "a very, very slow process".

He said the conditions at the one sq-mile site had continued to deteriorate, with the rain turning the already dangerous debris field into "quicksand".

No survivors have been found since the day of the mudslide.

The victims

Authorities have so far identified 18 victims including Christina Jefferds, 45; Stephen Neal, 55; Linda McPherson, 69; Kaylee Spillers, 5; William Welsh, 66.

Ms Jefferds, who the Seattle Times reports was a dental office manager, died of blunt impact injuries, says the medical examiner.

Family members have told local media that searchers also discovered the body of Ms Jefferds's four-month-old granddaughter, Sanoah Violet Huestis, whom she had been babysitting at the time of the mudslide.

Nichole Webb Rivera, 39, has not heard from some of her family members since the disaster struck.

Her 20-year-old daughter, Delaney Webb, was visiting Ms Rivera's parents for the weekend with her fiance Alan Bejvl, 20, when disaster struck.

Media playback is unsupported on your device Media caption Snohomish County Fire Battalion Chief Steve Mason explained on Friday what was happening at the site

The couple planned to wed on 16 August at Ms Rivera's parents home on the river, Ms Rivera said.

Her parents, Thom and Marcy Satterlee, were married 41 years and had lived in the area for three decades.

"If they could choose a way to go out, it would be like that, really fast and in the place they loved. Together," she told the BBC last week.

The mudslide destroyed about 30 houses, temporarily damming a river and leaving a square mile field of muck and debris in its wake.

The debris field is pocked with deep pits of water and strewn with sharp and dangerous wreckage, including fallen trees, propane and septic tanks, destroyed vehicles and smashed timber.

Image copyright Reuters Image caption The landslide left a cliff that is 600ft (182m) high, and a one sq-mile zone of destruction