Updated

A wildfire is spreading and forcing evacuations in Custer State Park in the Black Hills of southwest South Dakota.

The fire had grown to about 4 square miles by Monday afternoon. The state Wildland Fire Division says five homes in the park have been evacuated, though no buildings have burned and no one has been hurt.

The division says another concern is the historic Blue Bell Lodge, which is closed for the season. Officials say it's not currently threatened by the fire, but they're keeping an eye on the area.

About 200 firefighters are battling the blaze, which erupted Monday amid dry, warm weather. The cause of the fire is under investigation.

Custer State Park features hills with ponderosa pine and prairie. The park is closed, as are all roads in and out of the park.