Sirena Crosby, 38, is charged with first-degree murder. View Full Caption DNAinfo; Chicago Police Department

COOK COUNTY CRIMINAL COURTHOUSE — A West Side woman shot a stranger to death who slapped her 13-year-old stepson on a basketball court, prosecutors said Thursday.

The incident started Aug. 8 in the late afternoon as the boy played basketball near Springfield Avenue and Polk Street in the Garfield Park neighborhood, Assistant State's Attorney Bryan Grissman said during a bond hearing Thursday.

The 13-year-old got in an argument with 22-year-old Ireal Mitchell, and Mitchell slapped the teen, prosecutors said.

The boy went home and told his stepmother, Sirena Crosby, 38, what happened, Grissman said. Crosby went to the basketball court to confront Mitchell. After a short time, she returned home.

That's when she asked a man "to get a gun," Grissman said. She and the accomplice got into Crosby's silver Chevy Malibu and headed toward the basketball courts, according to prosecutors.

Crosby spotted Mitchell in the 800 block of South Springfield Avenue, Grissman said. As Mitchell walked by Crosby's car, she pointed a gun from the driver's side window and fired several shots — fatally striking Mitchell in his arm and back, police and prosecutors said.

Crosby then sped off, Grissman said.

The shooting was captured on surveillance footage, prosecutors said, and multiple witnesses were able to identify Crosby and her silver Chevy Malibu.

Cook County Judge Adam Bourgeois Jr. on Thursday ordered Crosby, of the 400 block of North Springfield Avenue, held in lieu of $3 million bail.

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