ATLANTA: A wannabe weatherman was jailed for arson after admitting he started a wildfire to draw attention to his selfie videos on Facebook, his town's police chief said Friday. Meanwhile, a Georgia sheriff appealed for help identifying the driver of a dark blue SUV last seen where other wildfires began. And in North Carolina, authorities suspect arson in more than 20 wildfires burning in a national forest.

"It's really too bad because he's not a bad kid — he's just misguided," said James Stephens, the police chief in Jenkins, Kentucky, where Johnny Mullins (21) was arrested this week on a second-degree arson charge.

"He likes to do Facebook videos and have people follow him on his 'weather forecast,' so that's pretty much why he did what he did," the chief said. "He enjoyed the attention he got from the Facebook stuff."

"He didn't realise how much danger he was putting other people in," Stephens added.

A teenager in Harlan County, Kentucky also was arrested for arson this week, and in Tennessee, authorities said Friday that Andrew Scott Lewis was charged with setting fires and vandalism causing more than $250,000 in damage and threatening homes outside Chattanooga.

No arrests were announced in most of the rest of the suspicious fires, which have been torching forests in and around the southern Appalachian mountains. The relentless drought across much of the South has removed the usual humidity and sucked wells and streams dry, making the woods ripe for fire.

Tens of thousands of acres have burned, about a dozen of the largest fires remain uncontained and many people to evacuate their homes ahead of fast-moving flames.

Law officers in Georgia's Rabun County suspect that someone started a series of small roadside fires Wednesday that eventually merged into the much larger blazes firefighters were working to contain on Friday, said Justin Upchurch, the county's assistant fire chief.

The Rabun County sheriff's office urged people to be on the look-out, saying the SUV was last seen in the area of the fires. The office was more emphatic in a separate Facebook post, asking residents to spread the word "and help us lock this criminal up!!!"

The area is less than 50 miles from North Carolina's Nantahala National Forest, where more than 20 wildfires that have burned more than 17,000 acres are all "being investigated for suspected arson," forestry officials announced in a status update.

There were 14 other wildfires burning on Cherokee Nation land in North Carolina, all under investigation by local law enforcement. A fire managers' update noted that the US Bureau of Indian Affairs is seeking information about fires on Indian lands through an arson hotline.

The US Forest Service announced Friday that the entire Cohutta Wilderness, which stretches across the Chattahoochee National Forest in Georgia and the Cherokee National Forest in Tennessee, has been closed to the public due to multiple fires there.

States of emergency were declared in some of the affected areas to facilitate state and federal spending on the response.

More than 5,000 firefighters and support staff from around the nation have joined the effort, said Shardul Raval, director of fire and aviation management for the southern region of the US Forest Service.

Smoke from the fires has made North Carolina's largest city a Code Orange zone for air quality, meaning anyone with breathing problems could suffer. The Charlotte Observer reports that the heavy haze and smoky conditions should make people limit outdoor activities.

That apparently isn't stopping organisers of this weekend's Charlotte Marathon. They said Friday that they do not expect the wildfire smoke to impact Saturday's races, which include a marathon, half-marathon, 5K run/walk, marathon relay and a kids 1-mile fun run.