Fire officials in Northern California reported further headway on Friday against the most lethal outbreak of wildfires in state history, as the death toll rose to 35 and teams with cadaver dogs combed charred ruins for human remains.

The wind-driven blazes, which erupted on Sunday night in the heart of California's renowned wine country, north of San Francisco, have destroyed an estimated 5,700 homes and businesses and forced the evacuation of at least 25,000 people.

With more than 200 people still missing on Friday in Sonoma County alone, and rubble from thousands of incinerated dwellings yet to be searched, authorities have said the number fatalities from the so-called North Bay fires would likely climb higher.