Nilson Hernando Vallejos Aguilera died that day at 6:30 hours at the Alejandro del Río Hospital due to multiple gunshot wounds with secondary anemia, as certified by the Medical Death Certificate from the Legal Medical Institute.

According to witness statements, Nilson Vallejos, a militant of the Juventudes Comunistas, found his apartment on Calle Catedral closed off days after September 11, 1973, with a sign indicating that the keys to the entrance should be collected at the Seventh Precinct of the Santiago Carabineros. That same day, he went to the police station to retrieve them.

At the end of September 1973, having had no news of him, his family members began searching for him. At the precinct, his detention was acknowledged, but they were informed that on September 20 he had been transferred to the Estadio Nacional. When they went to this prisoner camp, his detention was denied.

At the Legal Medical Institute, they learned of his death and went to the Cementerio General, where they were informed that he had been buried as a "John Doe" (NN) in Patio 29. After locating his remains, they transferred them to a family grave.

Considering the evidence gathered by this Corporation, the Superior Council reached the conviction that Nilson Hernando Vallejos Aguilera, while being held by State agents, was executed outside of any legal process. Consequently, it declared him a victim of human rights violations.