But it has only destroyed four buildings in the more sparsely populated area.
The largest fire, the Thomas Fire, burned more than 36,000 hectares, destroyed more than 150 homes and threatens thousands more in Ventura, about 80km north-west on Los Angeles.
Firefighters have been able to prevent the flames from spreading further since Thursday night and the fire was 80 percent contained Saturday morning, according to the Los Angeles County Fire Department. Three firefighters who were injured and admitted to hospital are in stable condition, the Los Angeles Fire Department said.
One LA resident, 84-year-old Patricia Moore, was loading her belongings into her auto when she told the AFP news agency: "Yesterday it was further north, but this morning we woke up and it was east of us". There is no word on containment at this time, Cal Fire said. The fire caused the temporary closure of the 405 freeway between West Los Angeles and the San Fernando Valley.
The Santa Monica Malibu Unified School District closed all of its schools Wednesday and Thursday.
Virginia Padilla, whose family owns a ranch in Sylmar, told reporters the fire killed at least 30 of the ranch's horses.
Another blaze north of Los Angeles, named the Creek Fire, was also only 5% contained and covered some 12,600 acres.More news: North Korea missile prompted Singapore Air plane re-route
Terrazas warned that the battle was likely to continue until at least Friday. Fire officials said 4,600 people were affected by the fire.
The Thomas Fire in Ventura County remains the largest of the current blazes, having spread as far as the Pacific coast, with satellite images showing large areas of scorched earth.
The LAPD was placed on a citywide tactical alert, which allows commanders to keep officers beyond the end of their shifts, giving them maximum flexibility in deploying resources.
Mandatory evacuations remained in place Thursday for the area north of the 210 Freeway, from Glenoaks Boulevard to Haines Canyon Avenue, as well as south of the 210 Freeway, west of Sunland Boulevard and Stonehurst Avenue, and north of La Tuna Canyon Road.
Evacuation orders were lifted late this afternoon for most of the Creek Fire-affected area, with the exception of parts of the Shadow Hills and Riverwood neighborhoods, as well as the Limekiln Canyon area.
A dozen evacuation centers were opened throughout the San Fernando Valley, and all were accepting evacuees, including those with pets. Twenty-nine horses died at a ranch in Sylmar, the Los Angeles Times reported.