Smoldering cow manure, hay likely caused fire in Stearns County, Minn.

Officials say smoldering cow manure and hay are believed to have caused a fire that damaged a building in Brockway Township, Minnesota.

According to the sheriff's office, a man was stacking cow manure in a building when it began to smolder.

Bales of grass hay from last year were also in the building, which the owner believes helped start the fire. 

No animals or other equipment were in the building. The damage to the building appears to be moderate.