Authorities in Casa Grande, Arizona (42 miles S. of Phoenix) are investing an unspecified “explosion” which took place at a Department of Economic Security building (Social Security Administration) on Florence and 2nd St at 8:00a local time. There are reports that an unidentified Hispanic male threw an object from a black Hyundai and quickly fled the scene. It is unclear whether the device exploded and caused the damage or was similar to a Molotov cocktail and burned the impact area at the rear of the building. People were inside the building at the time of incident, however no injuries were reported. The incident appears to be an isolated criminal event unrelated to terrorism.