DES MOINES, Iowa – Police have made an arrest after they say a man started a fire at the Polk County Courthouse late Wednesday night.

Nathan Warm, 35, is charged with third-degree arson in the case. Firefighters were called to the Polk County Courthouse at 5th and Mulberry around 10:40 p.m.

Sgt. Paul Parizek with the Des Moines Police Department said Warm set a small fire near a basement entrance and smoke entered the building. There was minor damage to the exterior of the building.

Sgt. Parizek said Warm was located at 6th and Walnut and arrested after being identified by witnesses. The criminal complaint in the case said matches were found in Warm’s coat pocket and he had been circling the scene.

Warm is being held in the Polk County Jail.