Northern California fires spur evacuations

The Poe fire burns in Butte County, California, on Friday.

SACRAMENTO, California (CNN) -- Two fast-moving fires forced the evacuation of hundreds of northern California residents on Friday, as firefighters struggling to contain the blazes battled gusty winds.

Nearly 400 homes remained evacuated in Calaveras County, about 60 miles southeast of Sacramento, as the Darby fire grew to 2,228 acres on Friday.

Meanwhile, 70 miles north of the state capital, the Poe fire swelled from 1,200 acres to 6,000 acres after erratic winds blew through the area Thursday night.

"We cannot give mandatory evacuations in Butte County," said California Department of Forestry and Fire Protection spokeswoman Shannon Sanders. "But that means that they (residents) are currently in the direction and spread of fire and if they don't leave now, their life is in danger."

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Wind speeds remain between 10 and 15 miles per hour -- "about the same as yesterday," according to Sanders. Firefighters had contained 10 percent of the blaze late Thursday night only to see their containment reduced to 5 percent as the fire spread on Friday.

"It's continuing to cross not only the control lines we've tried to establish but the natural barriers, such as roads ... and creeks," said Randy Lyle of the CDF.

Fire officials requested 50 more 20-person crews to help the 800 people now battling the fire, which has burned 15 homes and threatens some 400 others. Residents of 200 of those homes were evacuated.

Tom Sitter, a CDF fire information officer, said the Poe fire started Thursday and its cause is under investigation.

Three minor injuries have been reported. Two of the injured were firefighters, who experienced smoke inhalation. One was a private bulldozer operator who suffered hand burns.

Fire information officer Udell Smith said the Poe fire jumped Highway 70 -- which has been closed for several miles -- in several places.

Darby fire grows despite containment

The Darby fire grew an additional 400 acres Thursday night, although fire officials say the blaze was 40 percent contained Friday after reporting 10 percent containment the previous day. The containment was primarily on the western and northwestern fire lines.

Despite the progress, CDF officials remained cautious.

"Based on the way the fire developed and the potential threat to densely populated areas," said Incident Commander Tim Sappok, "an order for additional resources was placed based on the worst-case scenario."

Sappok ordered 50 additional engine strike teams, made up of 250 engines and 50 team leaders, through mutual aid channels. Additional strike teams are expected to arrive throughout Friday.

Four subdivisions were evacuated as the blaze threatened homes in the area. Another 2,000 homes could be threatened this weekend, and area residents have been told to prepare to evacuate, said Mary Pitto, a spokeswoman for the Calaveras County of Emergency Services.

Flames incinerated nearly a mile of flume -- open, wooded pipe used to carry water for about 10,000 people from Arnold to the City of Angels, Pitto said. During the estimated four months it will take to rebuild the flume, water may have to be trucked in, she added.

The fire began around 5 p.m. PDT (8 p.m. EDT) Wednesday in the Stanislaus River Canyon, but fire officials said they do not know the cause.