By CBSLA Staff

YUCAIPA (CBSLA) – As temperatures soared Sunday, air and ground fire crews battled the 400-acre Flats Fire in the Santa Rosa Mountains off of Highway 74 which has forced hundreds of evacuations.

The Flats Fire has burned 400 acres and was 30% contained as of Monday morning.

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“Pretty good, pretty good sized fire for this time of year,” Lisa Cox, a San Bernardino National Forest Spokesperson, said.

First reports came in just after 11 a.m. Sunday morning of a fire west of the Pinyon Flat campground in the Santa Rosa and San Jacinto Mountains National Monument.

(credit: San Bernardino National Forest)

The fire spread quickly prompting mandatory evacuation orders for residents of more than 100 homes in Pinyon Crest. Officials also closed Highway 74 Palowet and Ribbonwood drives. Evacuation warnings were also issued for Pinyon and Alpine Village, authorities said.

So far, the blaze is about 10% contained. It has destroyed two homes and damaged three others. Three outbuildings were also damaged. At least one firefighter has been injured and transported for medical evaluation.

Around 400 firefighters fought the flames today. Nightshift crews have now arrived and will continue to work on containment.

Investigators are still trying to determine what sparked the initial flames, but said there’s little doubt about what helped the blaze spread.

“So you’ve got critically low fuel moistures, you have the temperatures and then you’ve got the winds, ” Cox said.

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Experts are concerned that same triple threat is spread across the entire southland.

One new tool firefighters will have this year, as part of the new Quick Reaction Force Program, funded by SoCal Edison and launching Tuesday, are the use of three Chinook Heli-Tankers.

The Chinooks are the world’s largest fire suppression choppers, able to carry 3,000 gallons of fire retardant and, in an historic first, are able to fly any time day or night.

Cindi Monaco remembers last summer when the 10,000-acre El Dorado fire threatened, but never reached her family’s Oak Glen Home.

“Yeah, we were really, we were really scared,” Monaco husband told CBSLA’s Laurie Perez.

Because the burn scar is so large near the Monaco’s home, the family feels like there’s not much left to burn and that, at least for now, this risk of fire is low for them. Still, the Monaco’s said their thoughts are with anyone else who might be in the path of this year’s fires.

“With everything as dry as it is in California, we have our fire seasons and you just have to take the necessary precautions,” he added.

Evacuation orders for residents of Pinyon Crest are still in place, as is the road closure on Highway 74.

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