Published: Mar 20, 2011 9:19 PM EDT
Updated: Mar 20, 2011 6:28 PM EDT

PUNTA GORDA - Firefighters are investigating what sparked a brush fire that quickly grew to an estimated 100 acres near Punta Gorda early Sunday afternoon.

The fire broke out shortly after 2:00 and forced authorities to close an area of SR 31 at Bermont Road while they worked to contain the blaze.

A Charlotte County firefighter was airlifted to Lee Memorial Hospital after reportedly becoming trapped between two trucks at the scene.  Officials say he was treated and released Sunday evening.  He was airlifted as a precaution.

Authorities say no homes were threatened in the fire.

Most of Southwest Florida is below average for rainfall to date.  Officials say the brush fire danger is very high.