(Colorado Newsline) Officials have ordered road closures and mandatory evacuations in Gunnison County due to a fast-growing wildfire south of Crested Butte.

The Lowline Fire, first reported on Wednesday, was estimated at nearly 700 acres as of 9 a.m. Thursday, officials with the U.S. Forest Service said. The fire is burning on Gunnison National Forest land east of West Elk Peak.

“No containment has been achieved, at this time,” officials wrote in an update. “The primary objective for responders and managers today is structure protection, integrating additional resources into the response effort, and transitioning to (a federal incident management team).”

Governor Jared Polis verbally issued a disaster declaration and activated the Colorado State Emergency Operations Center in response to the fire early Thursday morning, state officials said.

The fire, which officials say was likely caused by lightning, started in the Squirrel Creek watershed about 10 miles south of Crested Butte and has spread to the southeast. The Gunnison County Sheriff’s Office issued mandatory evacuation orders for residents along County Road 727 and the Mill Creek watershed.

Ten structures in the immediate burn area were threatened, Forest Service officials said, and fire activity was expected to increase again throughout Thursday afternoon. An incident management team from the National Interagency Fire Center was due to take over command of response efforts Thursday evening.

Residents in a larger area to the southeast, along Eagle Creek Road, County Road 7 and County Road 818, were under preevacuation notices as of early Thursday.

Thanks in part to healthy snowpack and a wet spring, Colorado has had a slow start to the peak summer wildfire season, with only one fire to date exceeding 1,000 acres in size. But state fire officials warned last week that risks are increasing as hotter, drier conditions set in, and federal forecasters are predicting “above normal” risk for significant wildfires for southwestern Colorado in August.

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