LAS VEGAS (AP) - A massive mountain wildfire that made Las Vegas smell like a campfire destroyed six structures at a desert ranch and left two of the more than a thousand firefighting staff members with minor injuries, officials said Wednesday.
It wasn't immediately clear if any homes were 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.
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.
More than 270 additional firefighters arrived Tuesday to help battle the fire sparked by lightning July 1, bringing to 1,077 the number of people fighting the blaze about 25 miles northwest of downtown Las Vegas. One firefighter injured a knee on Tuesday and another camp support staff member suffered heat illness, Shelp 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. But the fire grew about 9 square miles (23 sq. kilometers) and overall containment dropped from 15 percent to 10 percent as erratic gusts of wind pushed flames up canyons, down the mountain and across state Route 157.
The main highway in and out of the evacuated Kyle Canyon area was briefly cut off, but crews bulldozed a fire line to protect the road, Shelp said. No homes in the canyon burned.
Overnight mapping put the fire at 25,524 acres (10,300 hectares), or almost 40 square miles (100 sq. kilometers), Shelp said.
"The big factor today will be what the wind will do, because we're still hot and dry," she said Wednesday.
Las Vegas daytime highs were expected to reach 107 degrees Fahrenheit (41.6 Celsius). The National Weather Service said there was a possibility of thunderstorms, although humidity during the morning remained a crackling-dry 11 percent.
With a visible pall over Las Vegas, building managers apologized to office workers about the smoky indoor smell and Clark County officials issued an air quality alert. 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.
Almost 100 structures were threatened, fire spokeswoman Lisa Ross said Wednesday, and 78 homes were evacuated after Lyon County sheriff's deputies went door-to-door Tuesday asking people in to leave Pipeline Canyon. Elected officials in Douglas County declared a state of emergency to enable the county to seek more state and federal assistance.
Fire spokeswoman Elayn Briggs said crews made progress overnight but worried that gusty afternoon winds could undo their efforts.
Associated Press writers Michelle Rindels in Las Vegas and Sandra Chereb in Carson City contributed to this report.
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