Aamer Madhani

USA TODAY

CHICAGO — Police were questioning a suspect Tuesday after a suspicious early morning fire left three children and an adult man dead on the city's South Side.

Chicago Deputy Fire Commissioner Arriel Gray said the victims of the suspected arson at the large apartment building included a 7-year-old girl, a 4-year-old girl and a 3-month-old girl. Police said they believe the suspect started the blaze following a domestic argument with someone in the building.

"After the incident, the offender returned to the building and set the rear porch on fire," said police spokesman Anthony Guglielmi.

The baby, who was identified by the Cook County Medical Examiner's Office as Melanie Watson, was pronounced dead at a nearby hospital, while the two other children and a man were found dead at the scene. Three other people were hospitalized, according to the Chicago Fire Department’s media office.

Witnesses saw several people jumping from windows to escape as the three-alarm blaze quickly spread across the second and third floors of the apartment building. Among them was the father of Melanie who jumped out of the window with the baby in his arms. The father, Michael Watson, was listed in critical condition at an area hospital.

Gray said arson investigators were trying to determine the exact cause of the blaze.

It took more than 200 firefighters to put out the blaze, Gray said. He added that “most stairwells were compromised” in the fire, making it impossible for firefighters to use them.

The two older girls who died in the blaze were found in the same apartment, while the man killed in the fire was found by firefighters in an adjacent apartment.

Lanita Smith, 25, a resident of the apartment, told the Chicago Tribune that she woke up to loud noises and thought someone was breaking in to her home. But then she saw her kitchen door was on fire.

“The fire was upstairs and downstairs,” Smith said. “My whole porch was on fire.”

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