CHICAGO (CBS) — A West Side man is charged with gunning down his neighbor earlier this week, after the victim asked him about an ill relative.

Richard Lewis, 55, of the 500 block of North LeClaire Avenue in the South Austin neighborhood, was charged with murder in the death of Curtis Connor, 54, of the 500 block of North Leamington Avenue, which shares an alley with the Lewis’ block, police said.

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Bond was set at $850,000 on Wednesday and a preliminary hearing was scheduled for Sept. 12, according to the Cook County Sheriff’s office.

Police say Conner was shot in an alley behind his home about 4 p.m. Monday after he walked up to the suspect, a neighbor, who was backing his car into a garage, according to Police News Affairs Officer Laura Kubiak.

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A witness working in the alley told officials he heard the suspect tell Connor, “Don’t sneak up on me like that,” after Connor and asked about the health of a relative of Lewis’ who had been sick, Kubiak said.

The suspect, still in his car, then took out a handgun and shot him in the chest for an unknown reason, Kubiak said. The suspect drove off but later turned himself into authorities.

Connor was pronounced dead at 6:51 p.m. Monday at Mount Sinai Hospital, according to the Cook County Medical Examiner’s office. An autopsy Tuesday determined Connor died of a gunshot wound to the chest and his death was ruled a homicide, according to the medical examiner’s office.

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The Sun-Times Media Wire contributed to this report.