The suspects have targeted at least four locations across the city since July 2.
The most recent heist happened Tuesday. Chicago police shared a video of the crime.
Investigators said a group of two to four suspects have shown up to businesses in a stolen gray or white Acura ADX.
When the suspects get inside, they demand access codes to safes and break glass counters to steal the jewelry inside.
During two of the incidents, victims were physically battered. In one incident, a victim was also robbed of his wallet and cellphone.
Chicago police said four recent crimes happened at the following locations and times:
- 4500 block of South Cicero Avenue around 9:28 a.m. on July 2.
- 1400 block of North Milwaukee Avenue around 10:03 a.m. on July 6.
- 4500 block of South Cicero Avenue around 4:15 p.m. on August 1.
- 2300 block of West Cermak Road around 10:57 a.m. on August 11.
No further information was available as Chicago police continue to investigate.
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