Police said the stabbing happened in the Woodlawn neighborhood's 1500-block of East 67th Street just after 7:30 a.m.
A 16-year-old girl grabbed a knife and stabbed a 35-year-old woman in the upper chest, police said.
Police said the victim was transported in critical condition to the University of Chicago Medical Center, where she was later pronounced dead.
The teenager is in custody and Area One detectives are investigating.
What led up to the stabbing was not immediately clear.
Police did not immediately provide further information.
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