A Cobb County jewelry store says a man stole a $28,000 diamond and walked right out of the front door.

Employees at D. Geller and Son on Cobb Parkway in Smyrna said the man is no amateur. He swapped the real diamond with a fake one while standing just feet from an employee.

The man spent two hours in the store earlier that day and then came back after closing to say he wanted to buy the engagement diamond he'd looked at earlier, according to employees.

Right when he was going to pay for it, assistant manager Candy Johnson says he told the staff he needed to step outside for a cigarette.

"We realized about as soon as he left that he had swapped our two-carat diamond with a cubic zirconia," Johnson said.

Johnson said by the time her staff went outside to find him, he was long gone.

"It's a stomach-dropping experience for sure," she said.

Footage from the store's security cameras is in the hands of Smyrna police. Employees say when the man made the swap, he did it in an area with no overhead cameras.

"At some point he was able to kind of do a sleight of hand," Johnson said. "He was definitely a professional."

When staff notified officials at the Jewelers Security Alliance in New York, the alliance noticed the suspect's face was familiar.

They gave Johnson a photo of what appears to be the same man outside a Virginia jewelry store, where he's accused of pulling off the very same crime.

Employees told Johnson said Monday was the first time they had ever seen the man in the video.

It's unclear if he even lives in Georgia.