The Cook County Medical Examiner identified the ninth victim as 14-year-old Cesar Contreras. Another 14-year-old remained in critical condition at Stroger Hospital. Family members said that teen is on life support.
Authorities have identified the other eight victims as 5-year-old Ariel Garcia, 11-year-old Xavier Contreras, 13-year-old Nathan Contreras, 16-year-old Victor Mendoza, 3-month-old Amayah Almaraz, 3-year-old Alanni Ayala, 10-year-old Giovanni Ayala and 5-year-old Gialanni Ayala.
The blaze broke out in a coach house in the 2200-block of South Sacramento Avenue. A neighbor came home around 4 a.m., saw the smoke and called 911.
Relatives said the victims are from at least two families.
Chicago Fire Commissioner Jose Santiago said it was the city's deadliest fire in a decade. And additional 30 people were displaced.
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"We have not had this in many, many years, this amount of fatalities and injuries in one location," said Commissioner Santiago said.
The cause of the fire is still under investigation, but was not electrical in nature and was not arson.
Investigators believe the fire started in an enclosed porch at the back of building.
That enclosed back porch of the coach house was known to be a spot where fireworks activity and smoking has taken place, officials said.
Investigators said there were no working smoke detectors in the home and no adults appear to have been present at the time of the fire.
The Department of Children and Family Services is now investigating allegations of neglect involving the children. Officials at DCFS said they have had prior contact with three of the families involved, but do not currently have any open cases.
"Ponder that for a second," said 12th Ward Alderman George Cardenas today. "Leaving an infant, three months old, in the hands of a sixteen year old, the oldest. And you have a 3-year-old, a five-year-old, a nine-year-old, a ten-year-old. What were they thinking?"
Alderman Cardenas says his office has working non-stop trying to help them all.
"School starts Tuesday. We need to get school supplies. We need to get clothing to the children that were displaced as well. We need to get families in housing," he said.
According to the Building Department website in Chicago, the building failed its last inspection in June due to electrical issues.
A statement from the department said, "The Department of Buildings inspected 2224 S. Sacramento Ave. on June 8, 2018 in response to a complaint from a tenant. As a result of this inspection, the building was cited for two electrical violations, one for grounding in the front of the building and one for an illegal electrical cord going from the front building to the coach house, and a court date is set for September 24, 2018."
The landlord and his family dispute the claims that the home was unsafe.
"There was something that was exposed, just a little bit. But it was fixed on Friday," said Brandy Hernandez, the landlord's daughter.
The landlord and his family showed ABC7 the most recent violations for issues with electrical wiring. The notice is dated July 24.
They were cited for an unapproved cord outside of the building, labeled dangerous and hazardous, and asked to install a bonding conductor.
He said that work was done. The Department of Buildings has not confirmed as of 11 a.m. Monday.
The owner also claimed that there were working smoke detectors and that inspectors were out at the property several times and they were never cited for issues with safety alarms.
Marcos Contreras lost two brothers and two sisters in the fire, along with three cousins.
"I don't even know how I'm going to wake up and continue life, knowing that my brothers and sisters are six feet underground," Contreras said.
The Cook County Medical Examiner began conducting autopsies Monday. A spokesperson said the cause and manner of death for all eight victims is pending investigation of the origin of the family.
A memorial to the victims grew outside the home throughout Monday.
A GoFundMe page has been set up to help the families with funeral and burial costs.
"We want to collect the most possible to help them," said Reverend Ramiro Rodriguez Monday.
Representing the Amor De Dios Methodist Church, Rodriguez says they're collecting supplies for the survivors and raising much needed money for the children's funerals.