CHICAGO (CBS) — The three men charged with luring 9-year-old Tyshawn Lee into an alley in the Auburn Gresham neighborhood and killing him execution-style will go on trial in April, more than three years after the boy’s death.

Cook County Judge Thaddeus Wilson scheduled jury selection to begin on April 22 for the trial of 25-year-old Kevin Edwards, 25-year-old Dwright Boone-Doty, and 30-year-old Corey Morgan.

Police have called Tyshawn’s murder a “targeted assassination.”

Tyshawn Lee, 9, was fatally shot in the Gresham neighborhood. (Courtesy: Karla Lee)

Chicago police and Cook County prosecutors have said the three men killed Tyshawn on Nov. 2, 2015, in retaliation for the gang-killing of Morgan’s brother, Tracy Morgan, who was gunned down three weeks before Tyshawn was slain. Tracy Morgan’s death was tied to Tyshawn’s father, and Morgan’s mother was wounded in the attack.

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Boone-Doty allegedly planned to torture Tyshawn by cutting off his fingers and ears. He allegedly lured Tyshawn away from the basketball court at Dawes Park, near 80th and Damen, by offering to take him to a store, and then shot him multiple times in an alley.

Prosecutors said Boone-Doty originally planned to kill Tyshawn’s grandmother, and to torture Tyshawn, because Tyshawn’s father, Pierre Stokes, was a member of a rival gang.

Police and prosecutors said both shootings stemmed from an ongoing gang war between the Terror Dome faction of the Black P-Stones and the Killa Ward faction of the Gangster Disciples.

Dwright Boone-Doty (left), Corey Morgan (center), and Kevin Edwards (right) are charged with first-degree murder in the execution-style shooting of 9-year-old Tyshawn Lee. (Source: Cook County Sheriff)

Authorities said on Oct. 13, 2015, 25-year-old Tracy Morgan was shot and killed while sitting in a car with his mother, who was shot in the arm. Morgan’s brother, Corey Morgan, planned to retaliate. He and his two co-defendants allegedly went out daily after that shooting, armed with guns, seeking retaliation.

On Oct. 18, 2015, Boone-Doty and Edwards allegedly spotted 19-year-old Brianna Jenkins and 20-year-old Deshari Bowens sitting in a car near 78th and Honore, and believing Bowens was a rival gang member, Boone-Doty walked up to the car, and fired multiple shots, killing Jenkins and wounding Bowens.

Then, on Nov. 2, Boone-Doty, Corey Morgan, and Edwards were still seeking retaliation when they arrived at Dawes Park, at 80th and Damen, and spotted Tyshawn playing with a basketball in the playlot, according to prosecutors. Morgan and Edwards drove off in an SUV while Boone-Doty stayed behind.

Tyshawn put down his basketball and began playing on the swings at the park, and Boone-Doty walked up to him and offered to take him to the store and buy him anything he wanted, prosecutors said. The two then walked into a nearby alley, where Boone-Doty allegedly shot Tyshawn multiple times at close range.

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Morgan and Boone-Doty were arrested about two weeks after Tyshawn was killed. Edwards was arrested six months later in downstate Danville.

Authorities have said Boone-Doty admitted his role in Tyshawn’s death, and said when he shot the boy, he “seen that bitch go in his head.”

Edwards’ public defender has said he was a special education student, and doesn’t have the mental capacity to plot the execution-style murder.