Chicago Mayor Rahm Emanuel and city health officials are asking the public to help stop illegal cigarette sales.
The Chicago Department of Public Health on Monday said it would offer a $100 reward to residents who report illegal sales that result in a conviction.
Licensed retailers may sell cigarettes in packs or cartons to people age 18 and older, and all packs sold in Chicago must have two visible stamps -- one from the State of Illinois and one from Cook County.
If both stamps are not on a cigarette packet when it's sold, then the sale is illegal.
Those who report the sale by calling 311 or by going online at www.CheckTheStamps.org could be eligible for a reward.
Emanuel says the primary goal is to keep kids from smoking.