More than 200 firefighters from Arizona and Oregon joined the fight Thursday against a group of fast-growing wildfires in southeastern Washington, and officials said they still need more help.

"The call has gone out," said Louise Day, fire information officer at the Columbia County fires. "The growth potential for the fires is still extreme."

Two hundred buildings are threatened by the fires, which covered nearly 70 square miles near Dayton on Thursday — up from 53 square miles Wednesday. Two homes had been destroyed, 35 outbuildings had been damaged, and about 300 people had been urged to evacuate.

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Gov. Chris Gregoire declared a state of emergency Wednesday, allowing state agencies to send money and resources to help local jurisdictions battle the blazes.

Conditions were better for firefighting Thursday, with lower winds and temperatures. But forecasts call for higher temperatures and dry conditions over the weekend and into next week.

The governor took a helicopter tour of the largest fire, in the north-central part of the state, on Wednesday. Nearly 3,000 firefighters were assigned to the area.

"It's very rugged terrain," Gregoire said. "The firefighters go in and put up a line, and the fire will jump a mile over the line. ... We're just hoping now the weather cooperates."

In Walla Walla County, in southeastern Washington, some residents along Coppei Creek were urged to evacuate as three fires burned nearby.

Thirty-five residents evacuated from a nursing home in Dayton were allowed to return after smoke over the area had cleared, and residents of some of the 200 homes that were evacuated also came back, said Ray Steiger, an information officer.

In eastern Oregon, wildfires burned through tens of thousands of acres of grass, sagebrush and juniper. Most of the fires were started by lightning.

"It's been hectic," said Tara Wilson, spokeswoman for firefighting agencies south of Burns. "We are getting tired, and our crews are getting tired. Things are stretched pretty thin. We've just had too much of the high winds, and the fires are pretty erratic in their behavior. It's going to be a long fight."

In Utah, a firefighter who died while battling a blaze in the Fishlake National Forest was taken to the cemetery on a fire truck Wednesday.

More than 1,000 people, including Gov. Jon Huntsman, attended the funeral for Spencer Koyle, 33, who died Aug. 17. He was scouting a fire when it suddenly trapped him, authorities said.

"There were a lot of tears," said Susan Marzec, a U.S. Bureau of Land Management spokeswoman. The fire continued to burn Wednesday about 15 miles north of the funeral in Holden. It covered nearly 8,000 acres, or 12 1/2 square miles.

More than 7 million acres, about 11,000 square miles, have burned across the U.S. this year, well above the average of about 4.4 million acres by this time of year, according to the National Interagency Fire Center.