A total of 108 people have been reported missing or unaccounted for after a landslide in the northwestern US state of Washington, a local emergency official said Monday.

The confirmed death toll remains at eight after the massive landslide slammed "like a freight train" into a mountainside community, said Snohomish County emergency management chief John Pennington.

He stressed that 108 is the number of reported missing or unaccounted for, not necessarily actually missing after the disaster on Saturday.

But he did say there were a total of 49 dwellings of various types in the area hit by the devastating landslide, and that there were likely to have been more people at home on a Saturday than during the week.

"To date there are 108 reports of names of individuals who are either unaccounted for or missing," he said. "This doesn't mean that there are 108 injuries, or 108 fatalities, it's 108 reports," he told reporters.

"It was Saturday, and it was probably a higher number than you would see during a weekday," he said.

Previously, the number of people reported missing stood at 18.