PICTURES

UPDATE: Four dead in Washington state landslide, 18 missing

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
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 TRAN
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
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
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

OLYMPIA (REUTERS) - The death toll rose to four and 18 people were missing on Sunday from a landslide in Washington state that buried homes and cars under mud and debris up to 5m deep, authorities said.

Eight people were also injured when rain-soaked embankments along State Route 530 near Oso, Washington, about 90km northeast of Seattle, gave way on Saturday morning and washed out at least six homes.

Snohomish County Fire District 21 Chief Travis Hots said rescuers had found a fourth victim, but they had yet to recover the body.

"I am disappointed to tell you that after searching a very large area of that debris field on foot, we didn't find anybody alive. There was no sign of life," Hots told a televised news conference.

The tally of missing was likely to grow, he said. The rescue mission will halt at dusk because of treacherous, quicksand-like conditions, and will resume at dawn on Monday, Hots said.

Washington Governor Jay Inslee flew over the area on Sunday.

He told the news conference, "I have a sense that we're going to have some hard news here."

The slide occurred in the foothills of the Cascade Mountains along the Stillaguamish River. The slide covered about 2.6 sq km and left mud, rock and debris up to 5m deep in some places.

It blocked the flow of the river, creating floods and a backup of water behind a natural dam of mud and debris, but the threat to people downriver had begun to ease, Inslee said.

The highway was closed in both directions, with no timeline for it to be reopened, he said.

The Snohomish County sheriff's office has asked people affected by the slide to report to the Red Cross so an accurate count can be made of the missing.

Washington state Lieutenant Governor Brad Owen on Saturday evening declared a state of emergency in Snohomish County.