(Radio Iowa) – Some Monona County residents in northwest Iowa have been warned they may have to evacuate as a large grass fire continues to burn there. County Emergency Management director, Patrick Prorok says the fire expanded after a small building caught fire Thursday afternoon in the southern part of the county.

“Since that time fire has spread to the north, it has gotten into Preparation Canyon and also Loess Hills Forest. Since that time 32-hundred acres has been burned up in Monona County, also reaching into parts of Harrison County,” he says. Twenty fire departments from two counties are trying to stop its spread. Monona County Sheriff, Kevin Ewing, says they let residents north of the fire know about the potential danger.

“I think most local area residents already know the situation I know a lot of people loaded up some valuables last night and are prepared to vacate the area if need be,” Ewing says. No mandatory evacuations have been ordered yet. Roadblocks have been set up to keep people away from the area.