Kenneth Thomas Bowen III, 24, was charged with seven counts of rape and one count of sexual battery, Clayton County Police Chief Kevin Roberts said at a news conference.
Roberts called the rapes "a cloud over our community."
DNA testing from evidence collected at the crimes scenes connected Bowen to the rapes. Police said they took him into custody at his job but did not disclose the name of his employer.
Roberts stressed that Bowen was never a police officer.
"Kenneth Bowen was never a certified police officer with this agency," he said. "He was hired by me in June 2018. He was also terminated by me on September 12, 2018."
Bowen was dismissed from the police academy for being absent without leave and being "untruthful," Roberts said.
"Had he not attempted to join the ranks of the Clayton County Police Department, it's questionable as to when we would have apprehended him," Roberts said.
Investigators eliminated multiple suspects through DNA testing, Clayton County Police Lt. Tom Reimers said. A review of 911 calls of suspicious people over the last several years led detectives to Bowen.
After obtaining his name and birthdate from a 2016 call, investigators found similarities between Bowen's photo and police sketches from descriptions given by rape victims, Reimers said.
A warrant for Bowen's DNA was obtained last week. After police surveilled Bowen at his job, they obtained his DNA during a traffic stop. The results came back Tuesday.