On the morning of Tuesday, April 21, 2015, 33-year-old Matthew A. Mizzie Williams was shot multiple times on the 900 block of 13th Street in Beaver Falls, Pennsylvania, just steps from his home. The shooting occurred shortly before 9 a.m.; neighbors, sanitation workers and schoolchildren heard the gunfire. Williams was flown to a Pittsburgh hospital but died later that day.

Police identified 25-year-old Christopher Kirkland as the suspect after investigators determined an argument between him and Williams escalated. Officers say Kirkland fired at least six shots during the confrontation. Kirkland was taken into custody, charged with criminal homicide and denied bond.

In May 2016 Kirkland, then 26, apologized to Williams’ family at sentencing, said he did not intend to kill Williams and claimed he did not know how to use his licensed firearm properly. He was sentenced to 12 to 30 years in prison for Williams’ death.

Did anyone in Beaver Falls witness the argument that morning or see either man in the days before the shooting?