(Fairfield Township)---The investigation is on into an office complex fire in Fairfield Township. The flames broke out just after 4:00am Monday at 6749 Gilmore Road, right across the street from Fiehrer Motors. A witness who first reported the fire said he heard explosions and saw heavy smoke arise from the building. Mutual aid was called in from Hamilton City, Monroe, Liberty, and West Chester Townships. No injuries were reported.