Published: Jun 04, 2010 10:19 PM EDT
Updated: Jun 04, 2010 7:21 PM EDT

PICAYUNE STATE FOREST, Fla. - Authorities are aggressively battling a 40-acre fire in the Picayune Strand State Forest. As of 5:00 p.m. Friday, it was about 30% contained, though the flames are said to be approaching the Fakahatchee Strand Preserve State Park.

No structures are threatened, but authorities say smoke may be problematic for drivers on Alligator Alley. Officials will be placing sigage on the roadway to urge motorists to use caution.

The flames were sparked by lighting Thursday.