A burned vehicle is seen on the Pacific Coast Highway in Malibu, California. Picture: Ringo HW Chiu/AP/African News Agency (ANA)

Paradise, California - Two monster wildfires burned out of control on Saturday in northern and southern California, having already killed at least nine people and forced hundreds of thousands to flee their homes.

President Donald Trump blamed the fires on forest mismanagement and threatened to withdraw related federal funding.

In Los Angeles County, the 35 000-acre (14 164 hectares) Woolsey Fire was threatening 75 000 homes and more than 200 000 people were under mandatory evacuation early on Saturday.

Some of the evacuation orders were for residents within the City of Los Angeles in the West Hills area. It was unclear how many homes have been evacuated within the City of Los Angeles.

Some 500 miles (800 km) to the north, nine people were found dead in and around the Northern California town of Paradise, where more than 6 700 homes and businesses were burned down by the Camp Fire. That made it one of the most destructive blazes in state history, according to California Department of Forestry and Fire protection data.

"This event was the worst-case scenario. It was the event we have feared for a long time," Butte County Sheriff Kory Honea said at a Friday evening press conference. "Regrettably, not everybody made it out."

Trump early on Saturday tweeted that "gross mismanagement of forests" was to blame for the two unchecked wildfires.

"There is no reason for these massive, deadly and costly forest fires in California except that forest management is so poor," he wrote in a Twitter post.

"Billions of dollars are given each year, with so many lives lost, all because of gross mismanagement of the forests. Remedy now, or no more Fed payments!," he added.

The remains of five of the victims in Northern California were discovered in or near burned out cars, three outside residences and one inside a home, Butte County's Honea said.

Another 35 people had been reported missing and three firefighters had been injured.

The flames descended on Paradise so quickly that many people were forced to abandon their cars and run for their lives down the sole road through the mountain town.

The Camp Fire, which broke out on Thursday at the edge of the Plumas National Forest northeast of Sacramento, has since blackened more than 90,000 acres and was only 5 percent contained as of nightfall on Friday.