Brothers Pedro Conrado and Juan Manuel Martínez Castaños, together with Ignacio Ibarguchi —all from Vizcaya— worked as door-to-door salesmen, selling books, records and other material for learning Basque. Whenever they went to Tolosa, they would have lunch together at the Beti Jai restaurant. On 24 June 1981, members of the Goierri unit of ETA mistook the three young men for police officers and opened fire on them as they were about to get into their car. Juan Manuel Martínez and Ignacio Ibarguchi were killed instantly; Pedro Conrado was severely wounded and died nine months later from his injuries. ETA initially denied any involvement in the attack, but finally sent the families a note acknowledging that the triple murder had been due to “a mistake”.
Conrado Martínez was 31 years old and married with one son. An artist by profession, he had fought against the dictatorship and had been active in the Comisiones Obreras trade union during his time as a metal worker. At the time of his murder, he was an active member of the Communist Party.