The cause of the fire is under investigation.
The flames started just before 2 a.m. in the 8200 block of Cornell Avenue.The Chicago Fire Department said they encountered a frozen hydrant and escalated the alarm, but the frozen hydrant did not hinder the response to the fire.
Firefighters took the woman out of the house with severe burns. She was found only a few feet from the exit, and officials said no smoke detectors were found in the house.The victim was taken University of Chicago Medical Center in critical condition, and later was pronounced dead. Update on Cornell fatal fire. CFD OFI has determined the most probable cause of this fire was a wiring problem and it will be classified as accidental. Please remember to check smoke detectors. They do save lives! 7