Kentucky fire investigators say last weeks fire that killed several horses at the old Riverside Downs racetrack was electrical. The State Fire Marshals office says a cord coming from an RC soda machine was plugged into an extension cord and the extension cord shorted out. The fire started Friday in an area near a washing stall. Six horses died in the fire. Nineteen other horses were rescued or escaped. Riverside Downs had a similar barn fire back in 2003.