ATLANTA -- Atlanta Fire and Rescue crews responded to a call on Friday evening about a possible HAZMAT situation at the Richard B. Russell Federal Building in downtown Atlanta.
Spokeswoman Janet Ward of the AFD said a letter containing a white powdery substance was found earlier that afternoon. HAZMAT crews tested the substance to determine its nature.
According to FBI special agent Stephen Emmett, investigators suspect the letter is related to two other threatening letters received on Thursday and Friday at the Herald Gazette newspaper in Barnesville. FBI agents will continue to investigate each case.
Four people who encountered the substance were taken to Grady Memorial Hospital as a health precaution.