CHICAGO (CBS) — The body of an infant girl was found dead inside an apartment on the West Side, fire officials said Wednesday.

Seven-month-old Lamya Hampton was found dead in a car seat in an apartment in the 3700 block of West 13th Street in the Lawndale neighborhood shortly after 3:30 p.m.

The mother of the baby has been found and is being questioned by Chicago Police. Illinois’ child welfare agency said it has never before had contact with the family.

Two other children, a 2-year-old and a 6-year-old, inside the apartment were transported to Mt. Sinai Hospital for observation, police said.

A neighbor discovered the baby in the car seat inside the apartment, which appeared to be unheated. One of the infant’s older sisters had gone to the neighbor, saying the kids had no food, were hungry, and had been left home alone. The neighbor investigated and called 911.

Paramedics rushed the unresponsive infant to Mt. Sinai Hospital, where she was pronounced dead on arrival. Two older sisters were also taken there. They appeared to be okay.

Area Central Police are conducting a death investigation.

The Cook County Medical Examiner has still not determined what caused the death of the baby.

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