The Joliet Police Department has launched an investigation after employees discovered an unidentified white powdery substance near the front lobby area of the building. It was on Tuesday evening at 7:52pm that the Joliet fire Department was notified and called to the scene. The front lobby area of the Joliet Police Department was evacuated and closed off to the public. The substance was treated as a hazardous material until being successfully identified as a harmless household powder by the Joliet Fire Department. The incident remains under investigation.