LAS VEGAS — A massive mountain wildfire that cast a smoky pall over Las Vegas on Wednesday destroyed six structures at a desert ranch and left two people in the firefighting force with minor injuries, officials said.
One of the buildings that burned in the Carpenter 1 fire was a commercial structure at Prospect Springs, U.S. Forest Service spokeswoman Suzanne Shelp said. She didn't know if any homes were among the buildings destroyed on the ranch several miles from woodsy Mount Charleston hamlets where crews were protecting more than 400 homes, a canyon hotel and a scenic alpine lodge and cabins.
In northern Nevada, about 1,065 firefighters reported progress battling a fire that grew Wednesday to more than 27,000 acres, or about 43 square miles in the Pine Nut Mountains near Carson City and Gardnerville. Containment was increased to 65 percent, although fire managers said a voluntary evacuation remained for 78 homes in the upper Smith Valley area of Lyon County.
Fire managers north and south kept a wary eye on the weather, hoping that predictions of possible thunderstorms would bring more rain to quell flames than lightning to spark new fires.
Humidity rose to 20 percent and temperatures remained in the 80s on Mount Charleston near Las Vegas, where an army of 1,077 firefighters and staff members worked to surround and beat back a blaze covering almost 40 square miles of rugged mountainside and canyons. One firefighter injured a knee on Tuesday and a camp support staff member suffered heat illness, officials said.
Crews set backfires, cleared undergrowth and positioned more than 50 fire engines to protect homes in the Rainbow, Echo and Old Town areas in Kyle Canyon about 25 miles northwest of downtown Las Vegas. A day earlier, the fire spread about 9 square miles and overall containment dropped from 15 percent to 10 percent as erratic gusts of wind pushed flames up canyons, down the mountain and, briefly, across state Route 157 – the main highway serving the evacuated Kyle Canyon area.
Overnight mapping put the fire at 25,524 acres of pinyon, juniper and bristlecone pines in an area at elevations of from 5,000 to 9,000 feet above sea level. The National Weather Service said the possibility of thunderstorms would increase Thursday.
With a visible pall over the city, building managers apologized to office workers about the smoky odor and Clark County officials issued an air quality alert, the highest form of public warning. It warned of unhealthy air pollution levels and advised people with respiratory diseases, bronchitis and asthma to stay indoors.
The Federal Emergency Management Agency has promised to reimburse Nevada for 75 percent of the cost of the fire, which was growing by more than $1 million a day. Fire officials said late Tuesday the amount topped $6.2 million.
Senate Democratic Majority Leader Harry Reid spoke Wednesday on the floor of the Senate about the fires, telling colleagues that firefighters were working hard, "but the progress we were making was erased yesterday."
The wildfire near Las Vegas is the top firefighting priority in the West, fire officials said.
In northern Nevada, the cost of battling the Bison fire that started with a July 4 lightning strike climbed to $4.8 million. Almost 100 structures were threatened, and elected officials in Douglas County declared a state of emergency to enable the county to seek more state and federal assistance.
Among other wildfires burning in the West:
_ In Arizona, residents were allowed to return Tuesday to about 100 of the 200 homes evacuated due to a wildfire in Kearny, 73 miles southeast of Phoenix. Officials reported 5 percent containment of the fire after it burned about 300 acres of dense vegetation and one house since it was sparked by lightning Monday.
_ In Northern California, more than 800 firefighters battled a fire in the El Dorado National Forest west of South Lake Tahoe that spread to almost 1 square mile but was about 80 percent contained. A shed and an outhouse burned, but no homes were threatened by the fire that may have been sparked Monday by a broken axle from a motorhome towing a truck. All lanes along Highway 50 reopened Tuesday.
_ In Southern California, cooler and calm weather helped slow an 11-square-mile wildfire that destroyed at least 100 buildings at a mountain camp near Julian, 60 miles east of San Diego. The blaze was 40 percent contained Wednesday, and state fire spokesman Mike Mohler said a chance of thunderstorms could wet down hot spots. Evacuation orders remained in effect for 120 buildings, mostly empty vacation cabins, and campgrounds in the Cleveland National Forest remained closed.
Associated Press writers Michelle Rindels in Las Vegas and Sandra Chereb in Carson City contributed to this report.
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