Two threatening letters containing white powder and mailed to two places 60 miles apart could be related, the FBI said Monday.

No one exposed to a powdery substance in recent days has had any symptoms. But the results of lab tests on the powder found Friday in Atlanta were not available Monday, according to Stephen Emmett, special agent, in the FBI Atlanta office.

Earlier this year, letters containing the deadly poison ricin were sent to President Barack Obama, a U.S. senator, New York Mayor Michael Bloomberg and a judge in separate cases.

Friday night, mail room workers found a letter containing an unidentified powder at the Richard B. Russell federal building, prompting an evacuation, the U.S. Marshal Service said. Three Marshal Service employees were transported to Grady Memorial Hospital for evaluation, but all were released that night, according to Deputy Gretchen Fortin.

The day before, a letter containing a suspicious white powder was received at The Herald Gazette newspaper office in Barnesville, about 60 miles south of downtown Atlanta. Field tests conducted were negative on the substance in Barnesville, Emmett said.

"As soon as I pulled the letter out, I had powder all over me," Walter Geiger, co-owner of the Herald Gazette since 1979, told The Macon Telegraph.

Geiger, also the paper’s publisher and news editor, said he immediately washed with antibacterial soap.

“It was frightening, especially when you’ve got powder all over your hands,” Geiger said.

Lamar County police evacuated the building and surrounding area during the investigation, the newspaper reported.

On Friday, the Barnesville newspaper received a second letter, believed to be related to Thursday’s letter, Emmett said. However, there was no threat nor powder found with the letter received Friday, he said. Geiger did not open the second letter, instead allowing investigators to take control of it.

A package reported to possibly contain a powder Monday afternoon at the Veterans Administration building on Clairmont Road proved to be a false alarm, the FBI said.