FOLKSTON, Ga. — Firefighters were battling Sunday to prevent a fire in a southern Georgia wildlife refuge from spreading, authorities said.

The Okefenokee National Wildlife Refuge said in a statement that “extremely dangerous burning conditions persist” and that 11,000 acres have been consumed by fire in the past two days. The unincorporated community of St. George is under a mandatory evacuation order and Charlton County schools have been closed today. Wind gusts and dry conditions were raising the risk of the fire spreading.

The fire in total has burned 129,856 acres, and wind gusts and dry conditions were raising the risk of the fire spreading, the statement said.

Some 535 personnel had been assigned to fight the fire, along with 10 helicopters, 55 wildland fire engines, bulldozers and other equipment, the statement said. The fire is 12 percent contained. The wildfire was sparked by lightning April 6 and has since burned mostly within the Okefenokee refuge boundaries and some public forest land.