Police said the shooting happened in the Humboldt Park neighborhood near North Sacramento Boulevard and West Chicago Avenue around 3:20 a.m.
Someone inside a black SUV pulled up to two people and opened fire, police said.
A 59-year-old man, shot in the leg, was taken to Stroger Hospital in good condition.
The second victim, a female of an unknown age, was shot in the shoulder. She was taken to the same hospital in critical condition.
The shooter fled eastbound on Chicago Avenue in the SUV.
No one is in custody, and Area Three detectives are investigating.
Police did not immediately provide further information about the shooting.
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