Media playback is unsupported on your device Media caption A large rescue operation is under way following Saturday's landslide, as David Willis reports

At least eight people have been killed by a huge landslide in the north-western US state of Washington.

Rescuers pulled five bodies from the debris on Sunday, adding to three found on Saturday.

Officials say there are still a number of people registered as missing, but search teams said they had not seen or heard any signs of survivors.

The 54m (177ft) deep landslide destroyed 30 houses near the town of Oso, about 90km north of Seattle.

Rescue teams have only just been able to properly search the site.

It was deemed too dangerous to access the worst-affected areas on Saturday.

'Wall of mud'

An eyewitness told the Daily Herald that he was driving on the road and had to quickly brake to avoid the mudslide.

Image copyright Reuters Image caption The authorities say the landslide was caused by recent heavy rain

Image copyright Reuters Image caption Dangerous conditions are hampering the rescue effort

Image copyright Reuters Image caption The thick mud covered an area the size of a square mile

"I just saw the darkness coming across the road. Everything was gone in three seconds,'' Paulo Falcao told the newspaper.

Robin Youngblood, another witness, told the Seattle Times: "All of a sudden there was a wall of mud. Then it hit and we were rolling. The house was in sticks. We were buried under things, and we dug ourselves out."

Residents reported hearing cries from those trapped, but local fire chief Travis Hots said the dangerous conditions were hampering the rescue effort.

Search-and-rescue help came from across the state, including the Washington State Patrol and the Army Corps of Engineers.

The landslide cut off the city of Darrington and clogged the North Fork of the Stillaguamish River, prompting fears of severe flooding downstream if the build-up of water behind the debris breaks through suddenly.

The authorities say the landslide was caused by recent heavy rain.

More rain is expected in parts of Washington on Sunday, and some people have been advised to move to higher ground.

The area has had problems in the past with unstable land.