Thomson firefighters responded to a false alarm from the new McDuffie County Government Center about 5:45 p.m. Monday.
Crews stood by outside until other firefighters inside the building finished searching for the cause of the alarm about 6:30.
Capt. Raymond Brinkley, who was at the wheel of one of two trucks, said there was no visible or audible evidence of a fire alarm once firefighters entered the building. Nor was there any evidence of a fire.
Thomson and McDuffie County police also responded.
Levar Jones said he was the last civilian inside the building when firefighters arrived. "At least I think I was; it's like a maze in there," he said. Jones, who works for Progressive Communications in Milledgeville, Ga., said he was installing the voice-over-IP system, which he described as voice over the Internet.
He said he was not aware of any fire or other problem inside the building.
"They're going through closets, everything," Jones said as left the building and firefighters continued their search.
Government offices from the city of Thomson and McDuffie County have begun moving into the structure.
The district attorney's office moved to the Railroad Street structure last week.