Suspicious powder at Clayton police headquarters not harmful

Preliminary testing of the powdery substance discovered at the Clayton County police headquarters "concluded that there are no biological toxins that have been detected," authorities said Wednesday.

The powder led to a three-hour evacuation of the building at 7911 N. McDonough St. in Jonesboro on Tuesday. It was found around 8:30 a.m. in an envelope in an isolated part of the building.

The tests were conducted by the Georgia Public Health Lab. The FBI is still conducting its investigation, and the final results are expected within five days, police said.