The robberies happened:
- About 5 a.m. Oct. 17 in the 4300 block of West Montrose Avenue;
- About 5:45 p.m. Oct. 17 in the 4400 block of North Elston Avenue;
- About 5:30 a.m. Oct. 27 in the 4900 block of North Harding Avenue; and
- About 8:55 p.m. Oct. 27 in the 4300 block of North Pulaski Road.
In the incidents on Elston Avenue and Pulaski Road, three men and a woman entered the business and punched the victim, hit them with a metal object and cut them with a knife before stealing their property, police said.
In the incidents on Montrose Avenue and Harding Avenue, the same group pulled out a gun, a baseball bat and a metal object before stealing the victim’s property, police said.
Anyone with information is asked to contact Area Five detectives at 312-746-7394.