BOZEMAN, Mont. — CNN founder Ted Turner has a problem that can be solved only with shovel and flame. He is burying and burning bison.

Officials in Montana are working with employees at Turner's Flying D Ranch to inter or incinerate as many as 85 domestic bison that died from anthrax during the past few days. To contain the deadly disease, the state also has closed a nine-mile stretch of road leading to the ranch in southwest Montana.

The outbreak occurred naturally and is not the result of any human activity, said Steve Merritt, a spokesman for the Montana Department of Livestock.

"Unfortunately, this occurs fairly regularly," Merritt said Wednesday. "Every once in a while, it kind of pops up."

Employees at Turner's ranch just north of Yellowstone National Park noticed last week that some bison exhibited anthrax-infection symptoms, which include staggering, unconsciousness and convulsions. On July 30, a state veterinarian confirmed that the creatures had anthrax.

Turner, who a spokesman said was unavailable for comment Wednesday, issued a statement late last week pledging cooperation with Montana officials.

"I'm not the first rancher to deal with an anthrax outbreak, and certainly not the last," said Turner, who owns an estimated 45,000 bison on 15 ranches in seven states. "Other outbreaks have been successfully managed throughout the U.S. and Canada, and I am confident we will do the same."

Anthrax showed up in Montana herds last year and in 2005, Merritt said. Rangers in North and South Dakota also have reported anthrax outbreaks this year, he said.

There's a slight risk of anthrax spreading to humans, but the illness isn't likely to infect anyone living on or near the ranch, Merritt said. The disease springs from Bacillus anthracis, a bacteria that occurs in the soil and can lie dormant for decades. Drought, followed by heavy rainfall, often triggers an outbreak.

State officials infer that conditions at Flying D were right for the bacteria to strike, Merritt said. "In Montana," he said, "we have all kinds of weather."

Turner's bison, part of a herd estimated at 3,000 head, likely contracted the disease by grazing or drinking water that contained its spores, said Don Woerner, a Montana veterinarian who periodically treats Bos bison, the American bison. About five years ago, he hand-raised Sandy, an orphaned bison calf that grew into a bull now siring offspring in a herd near Billings.

Anthrax, he said can fell a full-grown bison in two days. "Once they get it, it's very hard" to curtail, said Woerner, who also is a member of the Montana Bison Association, an organization that promotes bison meat.

The disease can move quickly through a herd, too. "Often, you get a sudden onset of death," he said.

Montana officials are confident they've contained the outbreak, Merritt said.

Wednesday, they were splashing gallons of Clorox on ground where the bacteria originated to kill it, he said. They also were busy with shovel and flame.