Waukegan police Commander Wayne Walles says the clerk, who hasn't been identified, shot Starks several times as he tried to flee on a bicycle.
Starks, who was shot twice in the torso and once in the leg before collapsing, was taken to Vista East Medical Center where he was pronounced dead.
Walles said a second suspect is being sought in connection with the robbery. That man however, did not enter the store, but might have aided Starks.
