Chicago Police have issued an alert to business owners after a rash of cell phone store robberies.
Four robberies have taken place over the past three weeks and investigators believe they may be connected.
Police say anywhere from two to four masked men entered the stores, showed a small revolver to the clerk and demand money from the registers and the safe.
The robberies have occurred at the following locations:
Police urge store clerks to always be aware of their surroundings, report suspicious activity and to remain calm if approached by a robber.
Anyone with information about the robberies is asked to call (312) 747-8380.