At least three robberies have happened since October, with the most recent robbery happening this week:
- 4000-block of South Oakenwald Ave. on Oct. 4 at 6:45 p.m.
- 4000-block of South Oakenwald Ave. on Nov. 10 at 3:30 p.m.
- 1000-block of East 40th Pl. on Nov. 26 at 4 p.m.
Investigators said the suspect tells potential buyers to meet in the alley near 40th and Oakenwald on the city's South Side.
That is when a second person pulls out a gun and takes the victims' money.
So far, no one has been hurt.
Police said the suspects are described as males between 5-foot-8 and 5-foot-10 who wear dark clothing.
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