Story highlights The Valley Fire grows to some 50,000 acres

Four firefighters injured in Lake County, California, taken to burn center, Cal Fire says

(CNN) California Gov. Jerry Brown declared a state of emergency in Lake and Napa counties Sunday, as the Valley Fire continued to bring pain and loss.

His announcement, which will help expedite debris removal and waive fees to replace essential documents like birth certificates for those who've had to abandon their homes and belongings, came one day after four firefighters were injured.

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The firefighters were burned in the Valley Fire in Lake County, about 115 miles west of Sacramento. Cal Fire public information officer Daniel Berlant said on Twitter that they were transported to a Sacramento-area burn center for treatment.

"All suffered 2nd degree burns and are in stable condition at UC Davis Medical," he said. At least 1,000 firefighters were trying to battle the blaze, which began as a 50-acre inferno.

Update on the 4 burned firefighters from the #ValleyFire. All suffered 2nd degree burns and are in stable condition at UC Davis Medical — CAL FIRE PIO Berlant (@CALFIRE_PIO) September 13, 2015

By Sunday, the fire had grown to some 50,000 acres.

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