Francisco Guillermo Flores died that day at 6:30 hours, on a public street, from two gunshot wounds with exit points, one facio-cervico-thoracic and the other thoracic, as recorded in the Medical Death Certificate from the Legal Medical Institute.

He was detained on the morning of September 17, 1973, outside his workplace, the ELECMETAL factory located at Avenida Vicuña Mackenna and Calle Maule, by Ejército and Carabineros personnel who were conducting an operation at the site. His family managed to locate his remains on September 26, after an intense search in various hospitals and detention centers.

During that same operation, workers from the same factory were also detained: José Rosa Devia Devia, Miguel Alberto Fernández Cuevas, Juan Dagoberto Fernández Cuevas, José Maldonado Fuentes, and Augusto Alcayaga Aldunate, who were executed the following day.

Their cases were reviewed by the National Commission for Truth and Reconciliation, which declared them victims of human rights violations.

The ELECMETAL factory remained occupied by the military from September 11 until September 16, 1973, the date on which the factory's activities resumed. The following day, Carabineros and military personnel appeared again and proceeded to selectively detain several workers and employees, most of whom were union leaders.

Given the evidence gathered and the investigation conducted by this Corporation, the Superior Council reached the conviction that Francisco Guillermo Flores was detained and executed by State agents outside of any legal process. Consequently, it declared him a victim of human rights violations.