The fire started at about 2:21 a.m. on Saturday, when a man threw an incendiary device through the window of an apartment in the 3100-block of South Green Street, police said.
The Cook County Medical Examiner's Office identified the woman living in the apartment as 54-year-old Charnette Walker. She died at the scene, according to police.
A 12-year-old girl was also injured in the fire. The Chicago Fire Department took the girl to an area hospital, where she was last listed in fair condition.
Cordale Nichols, 37, has been charged with two felony counts of murder, one count of attempted murder and one felony count of arson, police said. He also received an annual gun offender registration citation.
Nichols was arrested about 45 minutes after the fire in the 2900-block of South Halsted.
A motive was not immediately clear.
Whether the suspect and victims knew each other is unclear.
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