(AP) After announcing increased containment on one of the biggest wildfires in California history, officials warned that communities remain at risk and the threat could increase as unpredictable winds whip up again.

Red Flag warnings for fire danger due to Santa Ana winds and a critical lack of moisture were extended, with a possible increase in gusts into the end of the week.

Evacuations continued Wednesday for the seaside enclaves of Montecito, Summerland and Carpinteria and the inland agricultural town of Fillmore.

Officials announced Tuesday night that crews had carved containment lines around one-quarter of the blaze straddling Santa Barbara and Ventura counties.

The so-called Thomas fire has burned over 900 structures, at least 700 of them homes, since it broke out Dec. 4. It stretches across nearly 370 square miles (958 sq. kilometers) of Southern California, making it the fifth largest in state history.

Elsewhere, fire officials announced that a cooking fire at a homeless encampment sparked a blaze last week that destroyed six homes in the Bel Air neighborhood of Los Angeles.

Arson investigators determined that the so-called Skirball fire near the world-famous Getty museum was started by an illegal fire at a camp near a freeway underpass, city fire Capt. Erik Scott said.

The camp was empty when firefighters found it, but people apparently had been sleeping and cooking there for at least several days, he said.

Back at the largest of the wildfires, firefighters protected foothill homes while the flames churned mostly into unoccupied forest land, Santa Barbara County Fire Department spokesman Mike Eliason said.

Rock and Roll Hall of Fame member Eric Burdon and his wife, Marianna, of Ojai were among the people who fled the smoke Tuesday. Burdon, a member of the 1960s British Invasion band The Animals, wrote on Facebook last week about having to flee and returning temporarily to find their home still standing with ashes all around.

"A week like this gives you the perspective that life is what truly matters," he wrote.

A photo accompanying the post showed his handprint and signature written in ashes.