Wary firefighters work ahead of blaze

'This is grueling for the firefighters. We're getting tired'

A firefighter carries a log from a fire line cut on the west side of Show Low, Arizona.

SHOW LOW, Arizona (CNN) -- A giant wildfire in east-central Arizona on Friday escaped firefighters' containment efforts in the south and northwest while they were concentrating on the opposite side of the 650-square-mile burn.

The inferno stretched to 417,000 acres as it jumped fire lines and burnouts in Apache territory near where the fire originated on June 18 -- and threatened to jump a highway in the northwest separating the flames from 30 miles of unbroken ponderosa pine.

"We're tying to get ahead of the fire and get to work," said fire information officer Jim Paxon. "We've got to build a 90-mile fire line, and we're not going to get that done today. It's going to take three or four days."

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In the meantime, though, Paxon said the communities of Heber and Forest Lakes were in danger.

"It's so dry the fire will take advantage," he said. "With just a little bit of breeze it will jump up and run."

It was virtually the same on the blaze's eastern end, where firefighters had struggled mightily -- and apparently successfully -- to keep the flames from the town of Show Low.

"Yesterday was the first blue sky we'd seen in nine days here," Paxon said from the command center at Show Low High School.

"And it sure is nice to hear birds singing. When it was real smoky in here it got real quiet."

More than 4,300 firefighters are battling the Rodeo-Chediski fire, which has devastated several communities and forced 30,000 people from their homes.

Late Thursday, their work had contained 10 percent of the blaze.

Paxon said fire officials were meeting with Navajo County officials Friday morning to discuss a timeline for allowing some of the evacuees back in.

And some of those who have lost their homes were expected to view the damage as early as Friday afternoon.

"But they won't even be allowed out of the van," Paxon said. "We've got to mitigate the hazards first."

Officials said 423 homes have been lost to the fire, which began as two separate burns that merged earlier this week to form a flaming monster that seems intent on defying firefighters' best efforts.

"This is grueling for the firefighters," Paxon said. "We're getting tired."

Both fires started on the Fort Apache Reservation and burned along the northern edge of Apache territory.

Bureau of Indian Affairs spokesman Walter Lamar said his agency was working in concert with the FBI and U.S. Forest Service to determine who was responsible for the blazes.