An eight-year-old girl has died after being hit by a bullet as she walked through her neighbourhood with her mum.
Melissa Ortega died on Saturday afternoon after a gunman opened fire in Chicago's Little Village, where she lived.
The little girl, who moved to the US from Mexico last year, was rushed to the hospital with gunshot wounds to her head, but medics were unable to save her life.
Neither she nor her mother were the intended target of the shooting, police have said.
Melissa's death has sparked protests over gun violence in Chicago, with around 800 homicides reported last year.
The shooter got out of a car and opened fire as the intended victim, a 26-year-old man, walked out of a store at 2.45pm, according to investigators.
The man is in a critical condition after being struck in the lower back.
Following Melissa's death, the Chicago Teachers Union said in a statement: "Tonight, our union mourns the loss of another student from one of our school communities.
"This suffering is becoming all too familiar for many of Chicago's children and families, who our educators nurture and support every day.
"The Chicago Teachers Union sends its love to Melissa's family and the Zapata Academy community, and wish them peace and healing from this heartbreaking tragedy."
Chicago police superintendent David Brown said his team “will not rest" until the killer is caught.
He posted on Twitter : “The tragic and senseless murder of eight-year-old Melissa has shaken our city.
“There are no words of comfort when a child’s life is cut short. There are no words that can describe the grief of a family.”
Crisis responder Andrew Holmes called on the gunman to give himself up, ABC7 reports. Mr Holmes said: "You discharged that weapon on a little 8-year-old girl. I don't care who your targets were.
"You targeted that little girl. Because if you weren't targeting that little girl, she would still be living here today."
He continued: "I'm asking that area over there and any individual that knows anything about this shooting, stand up for this baby! Let's give this individual up.
"The baby is coming out of this hospital riding to the medical examiner's office. This should've never happened!"