The death toll from a devastating landslide in the US state of Washington remains at 14 but is expected to rise, with many more people missing, officials say.

The number of people unaccounted for after Saturday’s disaster still stood at 176, although officials stress that could include some double-counting and people who turn up safe and sound.

On Monday the confirmed death toll rose from eight to 14 following the mudslide which hit the town of Oso in Snohomish County, 95 kilometres north of Seattle.

“We’re expecting that number to go up throughout the day,” said Snohomish County fire district chief Travis Hots at a morning briefing Tuesday.

A total of 49 dwellings in the rural town northeast of Seattle were hit by the wall of mud, rocks and trees, which also destroyed part of a highway.

PHOTO: An aerial view before and after the Washington mudslide http://t.co/nfWYGNtcaM (Bing/AP) pic.twitter.com/3Wr5hAU6yL

— CBS This Morning (@CBSThisMorning) March 25, 2014

Three days on, officials insist it could still be possible to find someone alive, even though no survivors have been found since Saturday.

“I believe in miracles and I believe people can survive these events,” said emergency management chief John Pennington, adding: “They’ve done it before, they can do it again.”

President Barack Obama declared an emergency in the northwestern US state on Monday, ordering federal resources to join the local and state emergency services in tackling the disaster.

The local fire chief said the rescue and recovery operation will be a long one, but pledged to try to find every last victim.

“This is going to be a very long term event. This will be something that goes into the weeks,” said Hots, adding: “We’re going to do our very best to get everybody out of there.”