The shooting happened at about 10:41 p.m. at Clark and Adams, according to police.
A man walked in and began to rob the store. CPD said a 31-year-old man confronted the suspect as he was walking out of the store.
The suspect then pulled out a gun and shot the 31-year-old multiple times.
The victim was taken to Northwestern Hospital in critical condition with multiple gunshot wounds, police said.
Nobody is in custody.
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