Tragic stories have emerged of individual victims of a massive US landslide, as the confirmed death toll inched up Friday amid fears the eventual number dead will be much higher.

Ninety people remain missing after the mudslide crashed down on the Washington state town of Oso last weekend, in what could be one of the biggest landslides ever in the United States.

The confirmed death toll edged up from 16 to 17 on Friday, but the actual number so far found is believed to be at least 25, including eight bodies located in the debris by earlier in the week.

A total of 49 dwellings in the rural town were hit by the square-mile (2.5-square-kilometer) wall of mud, rocks and trees, which also destroyed part of a highway about 60 miles (95 kilometers) northeast of Seattle.

More than 200 rescue workers have been working in tough conditions for six days. A few survivors were found immediately after the mudslide, but none since last Saturday.

One of the most moving stories is that of Natasha Huestis, whose four-month old baby daughter Sanoah Violet are both among the confirmed dead.

Huestis had left her daughter with the infant's grandmother, who was looking after the baby at her home -- which was directly in the path of the massive landslide.

"Sanoah's name is Hawaiian. My mom, she came up with Sanoah's middle name, Violet," she said. "Sanoah Violet. Her name means mist in the mountains. And you know, she's in the mountains right now."

Gary McPherson, 81, and his 69-year-old wife, Linda, were sitting reading the paper next to each other in their Stillaguamish Valley home when the monster slide swept the entire structure for 150 yards.

He survived -- apparently because he was sitting in a heavy wooden chair, which protected him -- but his wife didn't.

"Before he heard people coming, he was able to dig a hole and see the sky," their 38-year-old daughter, Kate, told the Los Angeles Times. "The whole time, he was calling for my mom, who was right next to him, but she never responded."

Rain again hampered efforts Friday by emergency teams searching for bodies in the vast mass of sticky mud and debris, which obliterated nearly 50 homes.

Snohomish County District 21 Fire Chief Travis Hots had said on Thursday that he would announce a "substantial" increase in the death toll Friday.

But at two regular daily briefings Friday he and other officials said they could only announce deaths officially confirmed by the Snohomish County Medical Examiner's office.

"This is a sensitive situation for people who have lost their loved ones ... it's not as simple as saying 'This is the number,'" said Hots.

Washington state governor Jay Inslee has called for a moment of silence Saturday to honor the victims at 10:37 am (1737 GMT), exactly a week after the landslide occurred.

"I know that every Washingtonian holds in their heart the people of the Stillaguamish Valley and we all wish we could ease their pain," the governor said.