She’s thin, sometimes dressed in workout-style clothes. He’s older and pudgier, and has been seen wearing a newsboy hat. And they don’t appear to be together.

But federal investigators believe the pair is working as team to swipe diamonds and watches from jewelry stores across the Southeast, including two in Georgia. In each case, store employees have been forced at gunpoint into a back room, where they are zip-tied, according to the FBI. Then, using the employees’ keys to open display cases, the woman grabs expensive items and puts them into her shopping bag.

Although surveillance cameras have captured the two in various stores, it’s not known where the suspects head next, typically in a different vehicle each time. The stores targeted have typically been in outlet malls with quick access to interstates, according to the FBI.

On Monday, the pair hit their latest store, a Jared Vault store in Mebane, N.C. The FBI is asking again for help in identifying and locating the two suspects.

“Someone knows these people, and others have come in contact with them,” Lawrence Borghini, FBI special agent in Jacksonville, said in an emailed statement. “I’m asking the public to remain vigilant at all times and help us identify and locate these suspects before someone is seriously injured.”

The woman believed to be in her late 20s to 30s and is described as 5-foot-8 and 130 pounds, and the man as 6-feet and 250 pounds, possibly in his late 30s to early 40s, the FBI said.

“These suspects are armed and considered dangerous,” Borghini said. “If you encounter them directly, contact law enforcement immediately by calling 911.”

The FBI declined to release the value of all the items stolen. But according to some reports, the amount has hit $4 million.

The first two robberies linked to the suspects happened months apart last year in Georgia, according to investigators.

On April 29, the Jared Jewelry store in Woodstock was hit, foll.owed by the Zales Jewelry in Dawsonville on Aug. 5.

In the Woodstock robbery, the man was the prime suspect, but the woman appeared to be a customer in the store, The Atlanta Journal-Constitution previously reported. In Dawsonville, only the woman appeared in surveillance footage, Capt. Tony Wooten with the Dawson County Sheriff's Office said Wednesday. But investigators haven't ruled out the male suspect was still involved, possibly as the getaway driver, Wooten said.

Three more similar robberies followed on Aug. 11 in Panama City Beach, Fla., Sept. 2 in Bluffton, S.C., and in Sevierville, Tenn., on Oct. 16 the FBI said.

Anyone with information on the suspects is asked to contact the FBI at 1-800-CALL-FBI (1-800-225-5324).