CHICAGO (CBS) — Police say the wrong man was killed in a retaliation shooting in East Chicago over the weekend.

Willie Cook was shot to death in his car Saturday.

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His two-year-old son suffered minor injuries.

Police say the shooting was “payback” for a drug-related shooting last week, but they say Cook, a member of the Army Reserves, had nothing to do with it.

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Cook was stopped in front of his grandmother’s house in the 3900 block of Evergreen about 5:30 p.m. when police received reports of gunfire in the area.

Cook was pronounced dead at the scene. His son was strapped in a child restraint seat behind his father in the car.

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This is the second homicide in East Chicago’s Harbor neighborhood in less than a week.