Thousands under evacuation near Los Angeles as wildfire torches homes

Firefighters and police cleared residents from neighbourhoods near Camarillo before homes were set ablaze by embers blown 3.2 kilometres from the fire front, Ventura County fire department Captain Tony McHale said by phone from near the blaze.

"It's like trying to put out a blowtorch with a squirt gun," said McHale of the fire which began in a hillside canyon, then tore west, driven by Santa Ana winds.

Fuelled by abundant grass and scrub, with wind gusts up to 130 kilometres per hour, the blaze has burned over 5900 hectares, authorities said.

Climate scientists say warming temperatures have created wet winters that allow California's coastal chaparral - small trees, shrubs and bushes - to thrive. Record-high temperatures this summer have turned hillsides into unlit bonfires.

Several civilians were injured and a significant number of homes, businesses and other structures destroyed, McHale said, adding that it was too dangerous to enter the area to assess damage.

California Governor Gavin Newsom said the fire threatened 3500 structures.

Schools in Ventura County were closed through Friday due to the fires, according to the county's office of education.

The fire expanded in size after powerful winds came into contact with very dry air.

Southern California Edison began shutting off power to customers in areas where its equipment was considered at high risk of sparking a wildfire, according to the Los Angeles Times.

The United States is experiencing a strong wildfire year with 3.2 million hectares burned to date, compared with an annual, full-year average of around 2.8 million hectares over the last decade, according to National Interagency Fire Centre data. RNZ reported.

California wildfires have so far this year burned more than three times as much land as last year at this time when the state's fire season was more benign, according to Cal Fire data.