Gregory Petty, a 34-year-old African American man from Chicago, was shot and killed in the early morning of September 29, 2017. He was found unresponsive on the porch of a home in the 2200 block of South Kildare Avenue in the Lawndale neighborhood on the Southwest Side and died at Mount Sinai Hospital less than an hour after being transported there.

Police say a witness reported seeing 62-year-old Kenneth Cooper shoot Petty and then barricade himself inside a nearby home. Cooper, who lived on the same block, surrendered after a standoff and was charged with first-degree murder, unlawful use of a weapon and being a felon in possession of a firearm for a second time. He was denied bond and remained in custody, with a further court appearance scheduled for the following Monday.

What information can readers who knew Gregory or who were on that block that night share with the discussion?