Firefighters in Craig County are working to contain a blaze that may be burning up to 50 acres of forest along the Appalachian Trail, officials said.

More than 30 firefighters are working to contain the fire, which is burning about 12 miles northeast of Blacksburg on Sinking Creek Mountain in Craig County, according to Cindy Schiffer, district ranger for the U.S. Forest Service.

The fire has closed the Appalachian Trail between Virginia 42 and Virginia 621 but does not pose a risk to private structures or populated areas, Schiffer said. However, people near there may smell or see significant smoke.

While the cause of the fire is unknown, Schiffer said, it is clear that it has grown given the warm, dry weather and the abundant supply of natural fuel from dead trees that have been ravaged by pine beetle infestations.

"We're still in the 80s, and it's the middle of October," Schiffer said. "This isn't really normal, if there is a normal anymore."

The forest service first reported the fire early Sunday, and crews today will work on improving a fire line that has been established on the lower perimeter of the area affected by the fire. The line is a clearing about two feet wide where crews have removed any natural fuel that could spread the fire.

Crews are scheduled to survey the terrain by helicopter this afternoon to better determine where the fire can be contained in its perimeter farther up the mountain, Schiffer said.

It was unclear this morning how soon the fire could be extinguished, but it could be as early as the weekend, Schiffer said.