Residents keep watch on flames burning close to their home at the top of Louise Avenue in Los Angeles' Granada Hills area as efforts to control wildfires in Southern California continue Tuesday. (Reed Saxon/Associated Press)Strong winds Tuesday morning stoked three major wildfires in southern California that have destroyed dozens of homes, forced thousands to flee and killed two people.

Two fires in the San Fernando Valley in northwestern Los Angeles and another one at Camp Pendleton marine base near San Diego have burned a total of 6,000 hectares.

Firefighters keep watch as flames burn near homes in Los Angeles' Granada Hills area. (Reed Saxon/Associated Press)

More than 2,000 firefighters and a fleet of water bombers were battling the fires Tuesday, officials said. The blazes were threatening homes on the northern edges of the San Fernando Valley and forced the partial closure of two freeways, the Los Angeles Times reported.

The more ferocious of the two valley wildfires doubled in size to nearly 4,000 hectares Tuesday. Despite firefighting efforts to keep flames from subdivisions, about 3,000 people continued to stay away. The other valley fire, which burned 2,000 hectares several kilometres to the east, was declared 70 per cent contained Tuesday morning and most of the 1,200 residents forced to leave were being allowed to return to their homes.

The two deaths Monday were blamed on the fires, which have burned for a third straight day and have already gutted more than 49 structures, including mobile homes, and forced thousands of people to leave their neighbourhoods in suburban Los Angeles and farther south in northern San Diego County.

The notorious Santa Ana winds that blow in from the desert at this time of year recorded gusts up to 100 km/h in parts of the valley on Tuesday morning and were forecast to continue into Wednesday.

Firefighters worked through the night to try to establish a line around the fires, CBS News reporter Christina Penza told CBC News on Tuesday.

"Firefighters are trying to stay ahead of the fire as it continues on its path. There are actually two major brush fires that have been burning out of control and they've taken everything firefighters can do to try and get these under control," she said.

Santa Ana winds spread embers

Penza said the Santa Ana wind gusts have been a huge problem for firefighters.

"They can just grab embers from one spot and hurl them several hundred feet and start a whole new fire," she said.

Last October, fires stirred up by Santa Anas destroyed 2,196 homes, killed a dozen people and forced the historic evacuation of 500,000 residents in southern California in one week.

Penza said the two fires in the San Fernando Valley are burning in rugged terrain. One of the fires has destroyed 39 mobile homes.

In Camp Pendleton, more than 1,400 homes were evacuated at the huge San Diego County marine base and in nearby Oceanside, according to the base's website. The blaze had not yet destroyed any structures on the base.

"The fire wants to make its way to the coast, and we're going to do our level best to stop it," said Los Angeles fire department spokesman Brian Humphrey. "Two-thirds of our department is on the line."

Gov. Arnold Schwarzenegger has declared a state of emergency in Los Angeles and Ventura counties and urged residents to be prepared for the worst.

"Winds are causing fire conditions to change by the hour, which is why it is so important that residents in the areas surrounding these wildfires heed warnings from public safety officials to evacuate," Schwarzenegger said.

Of the two dead on Monday, one was a man who appeared to have been a transient living in a makeshift shelter, authorities said.

The other was a motorist who was killed about midday Monday when a tow truck rear-ended the driver's car on the freeway.

With files from the Associated Press