18 unaccounted for in deadly US landslide

Water flows into a ditch as a landslide blocks Highway 530 near Oso, Washington, on March 23, 2014. -- PHOTO: REUTERS 
Water flows into a ditch as a landslide blocks Highway 530 near Oso, Washington, on March 23, 2014. -- PHOTO: REUTERS 
Officials survey a large mudslide in this handout photo provided by the Washington State Police near Oso, Washington, on March 22, 2014. -- PHOTO: REUTERS/WASHINGTON STATE DEPARTMENT OF TRANSPORTATION
A general view of the area affected by a landslide near State Route 530 is seen in this Washington State Department of Transportation handout picture taken near Oso, Washington, on March 22, 2014. -- PHOTO: REUTERS/WASHINGTON STATE DEPARTMENT OF TRANSPORTATION
A landslide and structural debris blocks Highway 530 near Oso, Washington, on March 23, 2014. -- PHOTO: REUTERS
A landslide and structural debris blocks Highway 530 near Oso, Washington, on March 23, 2014. -- PHOTO: REUTERS
Concerned citizens listen as Washington Governor Jay Inslee addresses the media in Arlington, Washington as rescuers search for people still missing from a landslide on March 23, 2014. -- PHOTO: REUTERS

LOS ANGELES (AFP) - At least 18 people were unaccounted for more than 24 hours after a massive landslide slammed into a mountainside community killing three in the north-western United States (US), officials said on Sunday.

Eight people were injured, including a six-month-old infant, when mud, water and rock smashed into the rural town of Oso, north-east of Seattle, on Saturday, police and firefighters said. Six homes and much of a highway were destroyed.

"There is a full-scale, 100 per cent, aggressive rescue effort," Washington state Governor Jay Inslee told reporters, adding that helicopters, hovercrafts and rescue personnel had rushed to the scene.

"There's no missing piece in this rescue effort," he added, saying he had declared a state of emergency.

Snohomish County spokesman Shari Ireton told Agence France-Presse: "We are able to confirm we know that 18 people who may have been in the area are unaccounted for. We do not have identification for those people that we are releasing at this time."

The search and salvage operation in the mud-covered terrain was extremely dangerous, the unstable, rain-saturated surface putting emergency personnel at risk of further mudslides.

"Some (rescue workers) went in and got caught literally up to their armpits" in mud and had to be pulled out themselves, Mr Inslee said.

Some survivors had been hoisted to safety in the air, as others described the landslide as huge.

"All of a sudden there was a wall of mud" almost 8m high, Ms Robin Youngblood told The Seattle Times newspaper. "Then it hit and we were rolling. The house was in sticks. We were buried under things, and we dug ourselves out."

The landslide destroyed her home, she said.

Another survivor was driving on the highway just as the mudslide hit. "I was coming down the hill and I just saw the darkness," Mr Paulo Falco said on a local news report. "And everything was gone."

Rain has been especially heavy in the Cascade Mountains region in the past weeks, officials said. The forecast is for a break in the rain Sunday, but more heavy downpours throughout the week.

Authorities were keeping careful watch on a nearby dam, over fears pressure from the flooded river behind it could wash it away, inundating downriver communities.

However, Mr Inslee said geological surveys of the site suggested the water would be safely diverted over the coming days and evacuated residents were being allowed back home.

Senator Patty Murray gave assurances that federal resources would be made available, as she offered thanks to rescue workers and her prayers to the families of the ravaged community.

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