Investigators say a fire that destroyed four barns at the Kentucky state fairgrounds was intentionally set.

Four barns were destroyed and several others damaged in the blaze that was reported at about 2 a.m. Sept. 2. There were no animals in the barns, and no one was hurt.

Maj. Henry Ott, chief of the Louisville Metro arson squad, said a minor fire that broke out the afternoon before the major blaze erupted was quickly put out by fairgrounds staff and wasn’t reported at the time. It also has been ruled arson.

The state fire marshal’s office said Sept. 3 that investigators used dogs trained to sniff for fire accelerants in the investigation. Officials are still searching for tips on who might have set the fires