On an April morning in 2015, 25-year-old John Mengel was shot and killed inside a Glendale, Arizona condominium after a dispute with a former roommate. Police were called at about 8:45 a.m. following a 911 report of a shooting; Mengel was found with a gunshot wound and pronounced dead at the scene by Glendale Fire Department paramedics.

The man accused in the shooting, 22-year-old Justice Wolfgang Burkhart, initially ran from the scene on foot but was later returned to the condominium by a friend and taken into custody. Investigators say Mengel had recently moved out and had come back to the residence to collect some of his belongings when an argument with Burkhart escalated and ended in the fatal shooting. Burkhart was arrested and charged with first-degree murder.

If anyone knew John Mengel, lived in that building, or saw activity near the condominium that morning, any information could be important.