(CNN) -- Crews bolstered by out-of-state help worked in Texas on Monday to contain large wildfires responsible for destroying close to 100 homes and other structures, officials said.
"We are all doing the best we can," said Lisa Nugent, director of the Chamber of Commerce in Fort Davis, where the Texas Forest Service said fire has already destroyed 40 to 50 homes. "We have firefighters from all over the country."
She said it is too early for people to come to look at the damage.
"We don't want people coming back or visiting," Nugent said. The town is still in an "imminent danger of fire," with several fires still burning nearby. "I can see black smoke behind the courthouse," she said.
The fire in Presidio County has grown to 80,000 acres with only 10% containment, the Forest Service said early Monday.
That growth, according to fire operations chief Mark Sanford, came after the fire "made a 12-mile run on Saturday." Officials still don't know what caused the fast-moving fire, he said.
Despite the damage, Nugent said things could be much worse. "Tourism is huge" in Fort Davis, she said, but none of the tourist structures have been burned. The downtown and the historic fort buildings are unscathed, she said.
The blaze, known as the Rock House fire, is currently the largest fire burning in the United States and is just one of 10 fires burning more than 312,000 acres in Texas.
Another 34 homes have burned in a fire in Midland County that has consumed over 16,500 acres and that the state agency on Sunday described as "very active" and not at all contained, officials said.
A Red Cross shelter has been set up at Midland College for those displaced or otherwise affected by this wildfire.
"(Firefighters) can't outrun it," said Alan Craft, a spokesman for the state's Lone Star Incident Management Team.
Another large fire near Swenson has scorched some 103,000 acres in three counties, according to the state Forest Service. Spokeswoman April Saginor said officials believe the Swenson fire has been that large for a couple of days, but were not able to remap it until Monday.
As of Sunday night, the blaze across parts of Stonewall, Knox and King counties was totally uncontained despite the use of air resources, bulldozers, fire engines and other tools and personnel, a statement from the Forest Service said.
Official say this fire was caused by a man cutting a pipe.
There have been no evacuations yet related to another 60,000-acre blaze, this one in Potter and Moore counties near the city of Masterson. That fire is 50% contained but is still considered a threat to the towns of Dumas and Sunray, the Forest Service said.
Gov. Rick Perry renewed a disaster proclamation in effect for all of Texas' 249 counties -- even though major fires are occurring in only 13 of them -- to expedite assistance in case of new fires, his office said Sunday in a statement.
In addition to more than 750 personnel working with the Texas Forest Service, the governor's statement noted that two Blackhawk helicopters from the Texas Military Forces, bulldozers from the state transportation department and resources from 60 fire departments statewide were part of the effort.
Improved wind conditions over the past couple of days have helped firefighters in their battle, but dry conditions remain and still pose a problem, CNN Meteorologist Monica O'Connor said Monday.
Six new wildfires reported on Sunday were quickly brought under control, a Texas Forest Service statement said.
Authorities in the Lone Star State have responded to 6,831 fires over 643,000 acres since wildfire season began.
Texas is not alone, as wildfires are burning in large swaths of the Southwest and Midwest, fanned in part by dry, warm and windy conditions.
In the past few days, the National Weather Service has issued "red flag warnings" for New Mexico, Colorado, Kansas, Missouri, Oklahoma and Texas.
Oklahoma Gov. Mary Fallin on Sunday extended a state of emergency for seven counties. The designation authorizes state agencies to make emergency purchases needed to quickly deliver resources to local jurisdictions, the state's emergency operations center said.
Parts of Oklahoma remain under a "fire weather watch," which means that critical fire weather conditions are forecast to occur.
Many southern counties in Texas are under a "red flag warning," meaning conditions have created the potential for explosive fire growth.
The National Weather Service's website urges residents to exercise extreme care with respect to all outdoor activities that could inadvertently cause wildfires.
CNN's Dave Alsup, Stephanie Gallman, Mariano Castillo and Kara Devlin contributed to this report.