Armed thieves have stolen packages from delivery workers seven times since late September.
Two of the attacks happened on Tuesday during the day.
Police said the thieves have been seen driving a grey or white SUV, possibly a Jeep Cherokee.
The armed robberies happened at the following locations and times:
-9300 block of S. Hamilton Ave on Sep. 27 at approx. 2:09 p.m.
-8600 block of S. Indiana Ave on Sep. 27 at approx. 6:00 p.m.
-11800 block of S. Hale Ave on Oct. 1 at approx. 4:46 p.m.
-500 block of W. 122nd St on Oct. 4 at approx. 12:50 p.m.
-11500 block of S. May St on Oct. 4 at approx. 3:15 p.m.
-500 block of W. 95th St on Oct .15 at approx. 1:34 p.m.
-12700 block of S. Union Ave on Oct. 15 at approx. 5:54 p.m.
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