CAMARILLO, Ventura County (CBS/AP) — A fast-moving Southern California wildfire burning through coastal wilderness has nearly tripled in size since morning, growing to more than 43 square miles.

Ventura County fire spokesman Bill Nash says the 28,000-acre fire is burning new fuel in mostly unpopulated canyons. He says it’s 20 percent contained.

Parts of the Newbury Park community of Thousand Oaks are under mandatory and voluntary evacuations.

The fire was estimated to have burned about 15 square miles as of early Friday morning.

The wind-whipped fire erupted Thursday in the Camarillo area, threatening as many as 4,000 homes but only damaging 15.

After burning to the Pacific Ocean, a shift in winds caused the flames to reverse course and burn inland.

No injuries have been reported.

Firefighters from all nine Bay Area counties are heading south to assist in fighting the fire.

Alameda County sent 10 firefighters, according to Alameda County Deputy Chief Dave Lord. San Mateo County sent three engines, from the North County Fire Authority, Colma Fire Protection District and the City of San Mateo, with a total of twelve firefighters.

Around 30 engines from the Bay Area were sent in total, Lord estimated.

In response to the massive fire, the Federal Emergency Management Agency on Thursday authorized the use of federal funds to reimburse 75 percent of firefighting costs.

And at the state level, the California Emergency Management Agency deployed 15 strike teams, each composed of five engines staffed by fire personnel and an additional nine strike teams composed of local government engines, officials said Friday.

Cal EMA has also deployed strike teams to the Panther Incident in Butte County, the Yellow Fire in Sonoma County, the Summit Fire in Riverside County and the Cedar Fire in Butte County.

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