The event consisted of a clash between military officers, then under orders from Governor of Minas Gerais José de Magalhães Pinto, and Usiminas employees, who were outraged at the poor working conditions and the humiliation they suffered when they were searched before entering and leaving the company for their workday.

[4] On the morning of the 7th, about six thousand workers on strike in front of the Usiminas gate awaited the end of a meeting,[5] in which it was decided that the police cavalry would be suspended during the investigations into the aggressions of the previous day.

Just as Father Avelino and Geraldo Ribeiro, president of the union, were getting into a car to address the crowd, nineteen policemen on top of a truck started shooting at the workers,[6] officially resulting in eight dead (including a child on his mother's lap) and 79 wounded.

[10] Usiminas, a steel mill company installed in the then village of Ipatinga, belonging to the municipality of Coronel Fabriciano, in 1956, brought to the locality, besides the negotiation of land in large quantities,[11] basic infrastructure goods such as health establishments, leisure areas, transportation and communication.

[12] Its installation was the result of investments by Japanese businessmen and contributed to the formation of the current Vale do Aço Metropolitan Region, one of the main industrial centers in the state.

While the population of the entire region was growing due to the industrial activity, also influenced by Aperam South America (located in Timóteo, another village of Coronel Fabriciano), education in the city was precarious, with high dropout rates and illiteracy (over 50%) by the end of the 1950s.

[17] In addition, the infrastructure made available by the company was insufficient to meet the demand of workers from the region or who came from different areas of Brazil looking for work, as well as those who were not employed in the industry.

[15][18] The president of Usiminas at the time, Amaro Lanari Júnior, notes that "cases of madness began to occur in Ipatinga", as a result of this set of factors.

Sometimes security teams monitored employees in bars or in the streets of Ipatinga and, in case of suspicious attitudes, they communicated them to Usiminas' management to decide whether to remove or fire the worker.

[1] The Department of Political and Social Order (DAOPS) of Minas Gerais, which acted as a kind of intelligence service for Governor José de Magalhães Pinto, also had infiltration among the employees, as did the Brazilian Army, which feared that President João Goulart would establish a unionist republic.

[1] In early October 1963, undercover security forces reported to Usiminas the possibility of rising worker impatience and recommended that the company cancel plans such as the creation of a union controlled by itself and the mass dismissal of revolting leaders.

[20] On the afternoon of October 6, a Sunday, the first meeting of the Metalworkers Union of Coronel Fabriciano in Ipatinga took place, called after aggressions against workers for frivolous reasons, including crowd control and minor disagreements.

[2] Around 11 pm, an electrician was attacked by police forces after a group close to him resisted orders to dissolve a gathering of people in the Santa Monica (now Horto neighborhood) lodge.

The confrontation had been alerted to Robson Zamprogno, special delegate of the Ipatinga village and Cavalry Captain, who had been informed that the situation was out of control and needed reinforcement.

The religious asked that the soldiers withdraw and the 300 detainees be released, which in fact occurred, and it was agreed that a commission would appear at the Usiminas Central Office together with Robson and Father Avelino at dawn.

[27] In view of these events and in anticipation of the commission's meeting with the company's management, a crowd of about 1,500 workers formed shortly before 5 am near the gate, blocking access and inciting strikes.

The union president and Father Avelino proposed to remove the cavalry from Ipatinga, responsible for street policing, but this request was denied by the company and rebuked by Robson.

Captain Robson had also demanded that the troops leave without booing, which Geraldo Ribeiro had promised to try to do, but this would be almost impossible with the thousands of protesters in front of the gate, who were cursing and throwing stones at the soldiers who insisted on remaining armed.

[34] José Isabel do Nascimento was shooting at the military at the moment he was shot by a revolver,[35] and was taken to the Santa Terezinha Hospital (in the center of Ipatinga) and died on October 17.

[36] The then mayor of Belo Horizonte, Cyro Cotta Poggiali, arrived at the scene of the massacre at lunchtime in a truck loaded with drinking water and food.

At 1 pm, Captain Jacinto Franco do Amaral, who had come from Governador Valadares at Xavier's request to take over Ipatinga's policing temporarily, arrived by train on the Vitória-Minas Railway.

[37] Officially, the massacre ended with eight deaths and 79 wounded, but these numbers are contested, since there are many reports from family members of possible victims who were not accounted for, especially children who lost their father.

[41] Daniel Miranda Soares narrates in his article "O Massacre de Ipatinga" in the CEAS' magazine nº 64 of 1979 that more than three thousand people were wounded and 33 would have died by the following day as a result of their injuries.

[42] Among the eight deaths are José Isabel do Nascimento, the only one to photograph the massacre; the three-month-old girl Ângela Eliane Martins, who was shot in the arms of her mother Antonieta Francisca da Conceição Martins, who was taking her to the Usiminas outpatient clinic; five other industrial workers (Gilson Miranda, Aides Dias de Carvalho, Antônio José dos Reis, Alvino Ferreira Felipe, and Sebastião Tomé da Silva) and a tailor (Geraldo Rocha Gualberto).

There was still a resistance against the presence of military in some quarters, but at the suggestion of Father Avelino, the officers brought a music band that managed to bring the population closer to the security forces.

[48] This sketch was used as a strong argument in favor of the military and against the workers, however several information seen as uncertain would have been taken into consideration during the investigations, such as the unconfirmed presence of union leaders in the conflicts of the night before the slaughter.

Based on this project, only on October 7, 2004, the first process of compensation for the massacre (of the tailor Geraldo Gualberto's family) was approved by the Federal Government's Commission of the Dead and Disappeared.

[57] On October 7, 2013, on the fiftieth anniversary of the massacre – coincidentally also on a rainy Monday in the city – victims and relatives were heard by the National Truth Commission (CNV) in a public hearing at the Ipatinga Forum with the aim of gathering information about the episode.

[61] On October 7, 1989, on the occasion of the 26th anniversary of the episode, the Metalworkers Union of Ipatinga inaugurated the "7 de Outubro" Monument, which is located in the Bom Retiro neighborhood and reveres the deceased workers.

[61] On October 17, 2013, the Amnesty Commission of the Ministry of Justice inaugurated the "Monument to the Resistance and Struggle of Workers" at the Bible Square (Praça da Bíblia in Portuguese), in the center of Ipatinga, as well as in nine other Brazilian cities where there were political persecuted by the military regime.