Luis Marin, a 29-year-old Hispanic man, was shot dead on August 7, 2016, in the Humboldt Park neighborhood of Chicago. Marin was found with multiple gunshot wounds in the 1300 block of E. Luis Munoz Marin Drive and was pronounced dead at the scene. He had graduated from St. Francis de Sales High School and was studying criminal justice at Chicago State University; he had worked for the TSA until 2013.

Investigators treated the killing as a targeted shooting. Witnesses reported seeing a group of people running from the scene after the shots, and police said initial leads were scarce. Detectives later used surveillance footage and witness testimony to identify suspects; two people were arrested in the months after the murder, and one of those arrested faced felony murder charges.

Who knew Luis or saw anything in Humboldt Park around August 7, 2016 that could help fill gaps in the timeline?