Firefighters are responding to a rapidly growing wildfire in the Mitchell Lakes area north of Hermosa.

The fire was reported about 9:50 a.m. Friday. It started in the Iron King area and moved west into the Mitchell Lakes area.

The fire was 100 acres as of 11:45 a.m. and was spotting up to a mile ahead of itself, said Megan Graham, spokeswoman for La Plata County.

Durango Fire Protection District initially responded to the fire. A federal team is taking over command since the fire is located on National Forest land.

Multiple agencies are fighting the fire, including a federal helicopter and a helicopter provided by the Durango & Silverton Narrow Gauge Railroad, said John Harper, general manager of the Durango & Silverton Narrow Gauge Railroad.

La Plata County officials were considering pre-evacuation notices for areas on the west and east sides of U.S. Highway 550 north of Hermosa, said Butch Knowlton, director of county's office of emergency preparedness.

The column of smoke was so tall that fire responders were concerned it would collapse and cause spotting on the east side of Highway 550, according to scanner traffic. The pre-evacuation notice would be for homes from Baker's Bridge north to Electra Lake.

Emergency officials are asking drivers to stay off Highway 550, where traffic was backing up because people were pulling over to look at the plume.

This is a developing story. Check back with www.durangoherald.com for updates.