The Fremont County Sheriff’s Office reports a fire Monday afternoon at 901 Filmore Street in Sidney. The structure was unoccupied at the time and no one resided at the residence. Sidney, Hamburg and Tabor Fire and Rescue responded to the scene and one firefighter was treated for minor injuries and released from an area hosptial. The State Fire Marshal’s Office has determined the cause of the blaze as arson after a preliminary investigation. Anyone with information should contact the Fremont County Sheriff’s Office (712-374-2424).