On the morning of April 26, 2017, three men were shot to death in the Pine Lawn neighborhood of St. Louis County, Missouri. Authorities were called to the 4500 block of Rosewood Avenue around 10:13 a.m., and first responders found the victims in separate locations: one inside a black SUV, one on a nearby sidewalk, and one in the yard of a residence. Among those killed was 23-year-old Marquise Jamar Cooper; the other victims were identified as 29-year-old Calvin Walker and 29-year-old Andrew Green.

All three had sustained fatal gunshot wounds. The North County Police Cooperative asked the Major Case Squad of Greater St. Louis to lead the investigation, and detectives focused on two vehicles described as a white, older-model Chevrolet Impala with a black spotlight resembling a police vehicle, and a black Nissan Altima. No immediate arrests were announced and the suspects remained unknown; rewards were offered through regional crime stoppers as families pressed for answers.

If anyone has information about the vehicles, the occupants, or events that morning, please come forward.