On the morning of June 14, 1971, a mass shooting inside a red-brick house on Hazelwood Street in Detroit left eight people dead, including 27-year-old Carl Carrington Mounts Jr. Police described the apartment as a narcotics den; four men and four women had been shot at close range and some female victims were found with their hands bound. A large quantity of drugs and cash was left untouched, so investigators dismissed robbery as the motive.

Authorities quickly focused on Robert Gardner, described as a known heroin dealer and pimp, as the apparent primary target; the theory was that Mounts Jr. and the other victims were killed to eliminate witnesses. Neighbors reported hearing gunshots and witnesses later described four men fleeing the scene wearing windbreakers and tam o shanter hats, but a 20-detective investigation produced no arrests. The case remains unsolved. Anyone with information about Carl Carrington Mounts Jr. or the Hazelwood massacre is asked to come forward.