According to the radio, they're sending in some sophisticated testing equipment at this moment, and should know shortly what the stuff is. It sounds like it's going to turn out to be another hoax. But better safe than sorry.
BTW, Chambliss's office is NOT in Marietta but south of Smyrna in the Galleria area, inside the Perimeter. Less than a mile from my house.
2:00PM Update – Still reporting same information.
Homeland Security on the scene.
2ND HAZMAT team going in with detection equipment.