Officers responded to the Little Village neighborhood's 4300-block of West 25th Place just after 6:30 p.m.
Police said a 39-year-old woman was involved in an altercation with another woman on the street outside Corkery Elementary School after a crash two blocks away
That's when that person took out a gun and fired shots at the victim, striking her in the abdomen and buttocks, police said.
The victim was taken to Mount Sinai Hospital in critical condition.
Police said they are talking to a person of interest.
Area Four detectives are investigating.
Police did not immediately provide further information about the shooting.
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