About 9:10 p.m. someone at Kirk Hanson Field in Riverside reported smoke coming from behind the ball field in the Riverside Bluffs area.

Assistant Chief Dan Cougill with Sioux City Fire Rescue said that after Engine 8 arrived on scene they requested assistance from the department's grass rigs to access the area burning. Ultimately crews were able to access the area by foot and ATV from behind Sacred Heart School to extinguish the fire which appeared to burn 2 to 3 acres. Cougill says the fire appears suspicious because it's an area with just grass and trees.

The fire was under control about 10:00 p.m. and crews remained on the scene extinguishing hot spots.