Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

Firefighters battling Los Angeles' largest-ever fire continued to make progress Monday thanks to cooler temperatures, rain and lighter winds, officials said.

Although the La Tuna fire jumped from 5,800 to 7,000 acres, Los Angeles Fire Chief Ralph Terrazas said Monday, firefighters made big gains containing the blaze: They expanded the fire line from 10 percent Sunday to 30 percent Monday.

Still, Terrazas was cautious, saying the fire could continue to grow.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

"Fire operations are not over," he told reporters. "There's still a lot of work to be done."

The developments came after Gov. Jerry Brown, citing the thousands of threatened homes in the San Fernando Valley, declared a state of emergency in Los Angeles County on Sunday afternoon.

But by Sunday night, fire crews had made significant progress in beating back the blaze. One of Los Angeles's major thoroughfares — Interstate 210 — was reopened, and mandatory evacuations were lifted in Glendale and Burbank and in parts of Los Angeles.

All but 10 percent of the 1,400 people who were ordered to leave their homes in Los Angeles had returned home by Sunday night, NBC Los Angeles reported.

The fire, which began Friday afternoon near La Tuna Canyon, north of Burbank, quickly engulfed thousands of acres. Four firefighters were injured, and four houses were destroyed.

Among those who lost their homes was Craig Bollesen of Sunland, who told NBC Los Angeles that the fire — which appeared distant and slow-moving at one point Saturday — became "a ferocious, fast moving ... animal in a matter of 90 seconds to three, four minutes."

Several hundred yards of brush clearance did nothing to slow its advance, the station reported.

It was the second time that Bolleson's family had lost its home: His parents' house on the same lot burned during a kitchen fire in 1979. All that remained Sunday, the station reported, were piles of rubble, some toolboxes in what had been the garage and a single, unbroken serving dish.