SPRINGERVILLE, AZ --Flames from a mammoth forest fire licked the ridges surrounding the eastern Arizona town of Eagar on Tuesday afternoon, forcing the evacuation of about half the 4,000 residents as surrounding towns also prepared to empty. People started streaming out of Eagar as sheriff's deputies and police officers directed traffic. Flames were spotted on a ridge on the southeastern side of nearby Springerville and columns of orange smoke rose from the hills. Ash rained from the sky, which was filled with thick smoke, and when the sun peeked through, it was blood-red. Angie Colwell, her husband Mike and their two children were loading up their belongings as authorities ordered their Eagar neighborhood to evacuate. "We love the mountains and we're just afraid of what's going to be left after the fire comes through," the longtime resident said. The blaze has burned 486 square miles of ponderosa pine forest, driven by wind gusts of more than 60 mph since it was sparked on May 29 by what authorities believe was an unattended campfire. It officially became the second-largest in Arizona history on Tuesday. No serious injuries have been reported, but the fire has destroyed 10 structures so far. It has cast smoke as far east as Iowa and forced some planes to divert from Albuquerque, N.M., some 200 miles away. Joe Reinarz, commander of a firefighting team battling the so-called Wallow fire, told residents Tuesday night that the fire was within two miles of Springerville and Eagar. He said the blaze had skirted around Greer because crews were able to keep it out of the canyons surrounding the small resort town. Reinarz said several structures had burned in the Alpine and Nutrioso areas but he couldn't provide specifics. Crews were doing back burns Tuesday night and trying to build dozer lines around Eagar and Springerville to keep the flames away as law enforcement officers patrolled the evacuated areas. The Apache County Sheriff's Office issued the evacuation order for areas south of Highway 260 and east of Greer just before 4 p.m. The highway will be closed after the evacuation is complete. Eagar has about 4,000 residents, while Springerville has another 2,000. In all, about 7,000 people have been ordered to prepare for evacuation in recent days. Several tiny resort towns in the nearby Apache-Sitgreaves National Forest were evacuated earlier. Winds whipping the fire Monday drove the last holdouts from Greer. Earlier in the day, bulldozers scraped away brush and trees to create a barrier between the towns and the approaching flames in the surrounding mountains. Other crews removed brush from around homes and firefighters were sent to protect buildings from the flames. Thousands of firefighters, including many from several western states and as far away as New York, hope to keep the flames from getting into Springerville and Eagar, which sit in grassland at the edge of the forest. "The worst-case scenario is we're going to order an evacuation and the fire is going to burn up to the homes here," fire incident command spokesman Steve Miller said before the order was issued. "Or to wherever we stand and defend, hopefully not further than that." With a blaze as large as this being driven by unpredictable and gusty winds, putting the fire out is a gargantuan task. All fire managers can do is try to steer it away from homes and cabins by using natural terrain, burning out combustible material first and trying to put out spot fires sparked by embers blowing in front of the main fire front. New mapping showed that some fire breaks have held but the wildfire was still considered zero percent contained Tuesday night. Dozens of firefighters worked Tuesday alongside a stretch of Highway 191 about two miles outside of Springerville, burning combustible material such as vegetation along one side of the road in an effort to keep the approaching fire from jumping across and heading into town. Puffs of smoke billowed from underneath juniper and pinyon trees as flames licked at the trees. Jeff Brink, a member of an Idaho-based Bureau of Land Management fire crew, had spent the better part of Tuesday doing burnouts and making sure the flames stayed on one side of the highway while warily watching the weather. "Obviously, with these winds, when we're burning out the wind can shift," Brink said. The American Red Cross has an evacuation center at the high school about 15 miles west in Lakeside, Ariz. that can handle several thousand people, spokesman Mark Weldon said. The center was opened at Blue Ridge high after last week's evacuation of about 2,700 people from nearly mountain communities, but only about 50 were there before the new evacuations on Tuesday. Extra cots, blankets and comfort kits were rushed to the school early Tuesday as the threat heightened. Smoke from the fires was worst in the towns just north of the blaze, including Eagar and Springerville. But haze was being carried by a ridge of high pressure as far as central Iowa, said Kyle Fredin, a National Weather Service meteorologist in Denver. The smoke was also visible in New Mexico, Colorado, Nebraska and Kansas. Colorado health officials canceled a smoke health advisory Tuesday as smoke cleared from the southern half of the state. Two airliners headed to Albuquerque were diverted Monday night because of smoke and high winds. The state's largest blaze came in 2002 when flames blackened more than 732 square miles and destroyed 491 homes. A fire in 2005 burned about 387 square miles in the Phoenix suburb of Cave Creek and consumed 11 homes. Another major wildfire was burning in southeastern Arizona, threatening two communities. The 163-square-mile blaze has devoured two summer cabins and four outbuildings since it started May 8.