The shooting happened about 2:15 p.m. in an alley near East 78th Street and South Cottage Grove Avenue.
The teenager was shot several times by one of two people who confronted him, Chicago police Sgt. Antoinette Ursitti said.
The victim staggered behind a church near 78th and Cottage Grove and was taken to Jackson Park Hospital by ambulance, officials said.
The shooting may have been gang related, Ursitti said.
Police turned out in force in the neighborhood, with a swarm of officers in the area with M4 rifles, because, a police source said, the victim is the younger brother of a top member of the Gangster Disciples and police fear a retaliation shooting.
Officers were searching for the suspects in the area of 78th and South Champlain Avenue.
The 17-year-old boy -- identified by the Cook County Medical Examiner's office as Jeremy Brooks -- was shot at 2:16 p.m. in an alley near the 700 block of East 78th Street, police News Affairs Officer Veejay Zala said.
Two gunmen approached the teen and one fired in his direction -- striking him multiple times, police said. The suspects fled after the shooting.
Brooks, of the 7800 block of South Ellis Avenue, was pronounced dead at 2:30 p.m. at Jackson Park Hospital and Medical Center, according to the medical examiner's office.
A large number of gang-enforcement officers were sent to investigate, police said. The slaying is believed to be gang-related and may have been a retaliation murder.
Per Alderman Lyle and representatives of the 6th district police this WAS NOT an act of random violence but the settlement of "Beef" over a female.
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