Chicago police said the incident happened around 6:20 p.m. in the 2600-block of East 73rd Street.
According to CPD, a man walked into the store and pulled out a gun to start a robbery. A Good Samaritan who CPD said has valid FOID and CCL cards also pulled out a gun and shot the would-be robber.
The would-be robber fired back and struck a third person, the employee who he targeted to rob, police said.
The would-be robber was pronounced dead at the scene. The 64-year-old man who was shot by the offender was taken to University of Chicago Hospital in critical condition. The CCL holder was not injured.
"My grandchildren were upstairs and are terrified...so was I," said neighbor and witness Stephen Galin.
Police said three guns have been recovered from the scene. An investigation is ongoing.
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