At 10:01 p.m. on Tuesday, May 14, the Naperville Emergency Communications Center (ECC) received notification about an activated fire alarm at 450 W. 5th Ave. Naperville 911 (ECC) dispatched a single unit to the scene. Upon arrival NFD found activation of the sprinkler system and the odor of smoke. The assignment was upgraded to a general alarm consisting of 13 pieces of fire apparatus and 29 personnel, including an incident commander and incident safety officer, to the reported address.

After upgrading the alarm, the first arriving company deployed a handline and forced entry into the suspected fire unit. Fire companies ensured there was no fire extension into adjoining units and confirmed there were no occupants in the structure. At 10:23 p.m., the incident scene was deemed under control. Fire companies remained on the scene until 11:39 p.m. to ensure the occupancy was secure and there was no further fire hazard.

The Naperville Fire Department was assisted on the scene by the Naperville Police Department and the Naperville Transportation, Engineering and Development Department (TED). The Warrenville Fire Protection District, Lisle Woodridge Fire Protection District and Bolingbrook Fire Department provided station coverage during the incident. The cause is still under investigation. There were no injuries to any civilians or firefighters while operating on scene.