Updated

Chicago police said Monday they had identified the suspected triggerman in the execution-style killing of a 9-year-old boy that shocked the violence-scarred city this past November.

Dwight Boone-Doty, 22, was charged with first-degree murder in the death of Tyshawn Lee, police spokesman Anthony Guglielmi said.

The child was playing basketball in a park on the city's far south side on the afternoon of Nov. 2 when he was lured into a nearby alley and shot in the head. Seven .40-caliber bullet casings were found at the scene.

Police believe the killing was gang-related retaliation against the boy's father. Boone-Doty was being held on an unrelated gun charges in an unrelated case when investigators connected him to the murder.

Another man, Corey Morgan, was charged with murder in November in connection with Tyshawn Lee's killing. He had been arrested at the same time as Boone-Doty.

In addition to the Lee murder, Boone-Doty has also been charged with first-degree murder, attempted first-degree murder and aggravated battery with a firearm in connection with an Oct. 18 shooting that killed 19-year-old Brianna Jenkins and wounded 20-year-old Deshari Bowens.

Lee has also been charged with unlawful delivery of an illegal firearm in an unrelated case.

The Chicago Sun-Times reported that Boone-Doty was sentenced to five years in prison in July 2013 after being convicted on gun and drug charges. He was paroled in August 2015, three months before the Tyshawn Lee killing.

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