It happened late last month when the 83-year-old victim walked into a Walmart and was met by a woman who said her job was to help elderly shoppers.
The victim is in serious, but stable condition after being shot four times.
The Illinois State Police have taken a woman, who was believed to be involved with the robbery at a AT&T store, into custody.
Police say the suspects robbed a clerk at gunpoint and tied her up, before leaving with 25 to 30 new smartphones.
Two men tied up a clerk before stealing smartphones from a T-Mobile store in South St. Louis County.
Accused in string of armed hold-ups.
East Alton police say someone sprayed a clerk at Title Max, Saturday morning, then stole an undisclosed amount of cash.
Police use a Metrolink surveillance camera to catch a 17-year-old charged with robbery.
Two happened in north St. Louis County and the other in north St. Louis. Investigators are trying to determine if they were pulled off by the same criminals.
An AT&T worker is robbed of his cell phone and wallet shortly before noon Tuesday by a knife-wielding suspect.