Devastating wildfires laid waste to miles of land around California's scenic wine country, reducing hundreds of homes and businesses to smoldering ruins and leaving one person feared dead.

Fast-moving infernos raging in parts of drought-ridden northern California have forced thousands to flee over the past several days, state disaster officials said.

Four firefighters have also been injured as the blazes moved at alarming speed across the region, and there were so far unconfirmed reports of one fatality.

"The fires are spreading faster than I have seen in my 30 years," Mark Ghilarducci, the state's emergency services chief, told The Sacramento Bee newspaper.

Over 11,000 firefighters are battling 12 large fires across California.

Two -- the Valley Fire about 100 miles (160 kilometers) west of the state capital Sacramento and the Butte Fire about 100 miles to the east -- have been particularly devastating, together destroying 435 homes according to fire officials.

Governor Jerry Brown issued an emergency declaration for Lake and Napa counties -- wine-producing regions north of San Francisco -- due to the massive Valley Fire. Area schools were also closed on Monday.

- Ghost town -

Among the hardest hit areas is Lake County, named after the picturesque Clear Lake, a mostly agricultural area of pear orchards and vineyards, where communities have names like Spring Valley and Whispering Pines.

Lake County's village of Middletown, about 100 miles north of San Francisco was turned into a ghost town first, having been evacuated as residents fled the fast moving Valley inferno.

The town was then consumed by the blaze, with little remaining other than smoldering brick and stone after the buildings were burned down to their foundations.

Evidence of the deadly conflagration were strewn throughout the area in the aftermath the of the fire's destruction.

Burned out chassis of what once were cars were abandoned on the side of road, while charred trees, still standing, eerily stretched stripped, blackened limbs to the sky.

From a distance, the region's famed rolling foothills glowed red and orange from the fast-moving blaze.

"My heart goes out to all those who lost homes and businesses in the devastating fires in California," the state's senator, Barbara Boxer. said in a tweet.

"Praying for the safety of all."

The recent fires have been fueled by tinder-dry conditions across the western United States, which has been starved for rain for the past several years.

The prolonged dry spell has been exacerbated by record high temperatures, which many environmentalists blame on global warming.

- Nine times size of Manhattan -

Daniel Berlant, the spokesman for Cal Fire, the state firefighting authority, said early Monday that the Valley Fire so far has consumed 61,000 acres (24,685 hectares), and was only five percent contained with 1,200 firefighters mobilized to tackle it.

The 4,400 firefighters combatting the Butte fire have had more success. That blaze has consumed some 70,000 acres, but is now about 30 percent contained.

Together the twin blazes have destroyed an area nine times the size of Manhattan.

About 6,400 homes are still threatened by these monster fires, Berlant said overnight, although some evacuation orders linked to the Butte fire have been lifted.

Three other fires are scorching the earth in neighboring Oregon state and 10 further north in Washington state.

While temperatures are cooler than in the past week, conditions remain extremely dry, which allow fires to burn at a rapid rate.

Nearly 70 firefighters from Australia and New Zealand are assisting fire services in the western United States.

National Guard troops have also been called in to help.

Berlant said Cal Fire so has far spent more than $212 million since July 1 to fight fires under its jurisdiction.

The costs of containing other fires, such as those blazing in Sierra Nevada forests, are largely covered by federal agencies and not included in those figures.

The US Forest Service has spent an additional $1.31 billion battling fires and says it is approaching its record expenditure, from 2002, of $1.65 billion.