A fire Tuesday at Madison State Hospital's Kemp Hall has been ruled an arson, and a reward is being offered for information leading to an arrest.

Madison Fire Chief Steve Horton said he and Clayton Kinder, the south senior investigator for the Arson Division of the Indiana Department of Homeland Security, performed a post-fire investigation Wednesday.

Horton confirmed "multiple fires were set" in Kemp Hall which is unoccupied. A reward of up to $5,000 is being offered for information that leads to the arrest of anyone responsible for the fire. The reward is being provided by the International Association of Arson Investigators Chapter No. 14, the Indiana State Fire Marshal and property insurance companies in Indiana.

Crews responded to the Madison State Hospital around 6:20 p.m. with reports of smoke coming from the building.

Employees with the Madison State Hospital told authorities they saw two people leaving the Kemp Hall area moments before smoke was spotted.