FORT RANCH -- Firefighters contained a lightning-sparked wildfire in Box Elder County that spread to more than an estimated 5,000 acres by Thursday evening.
Between 30 and 40 personnel were fighting the blaze in the northern Promontory Mountains, many of them local volunteers from Box Elder County community fire departments.
Single-engine planes and a helicopter dropped water on the flames to aid them, said Jason Curry, public information officer with the Utah Division of Forestry.
"We still have a couple engines out here making sure nothing escapes, but we have 100 percent containment ... as of 6:30 p.m.," he said.
No injuries were reported, and no structures were damaged by the blaze, which started about 7:30 p.m. Wednesday.
In the early hours, structures near the Fort Ranch were threatened.
Crews "black-lined," or burned, the area surrounding the buildings to create a buffer between them and the oncoming fire.
Curry described the terrain where the fire is burning as "steep, rocky, rugged and very inaccessible by vehicles."
The blaze was able to spread very quickly late Wednesday night because of high winds blowing north, Curry said. As the fire continued into Thursday morning, firefighters expected a hard fight against more high winds in the afternoon.
"High winds would be a problem for us," Curry said Thursday morning.
But the winds never came, making containment easier. By 4:30 p.m., the fire was at 55 percent containment.
One thing that has helped in fighting the fire was the decision some time ago to plant what Curry calls "vegetative fire breaks," or plants with a high moisture content.
"The fire really slows down when it hits those plants, and that helps."