The Tlatelolco massacre is one of the darkest days in Mexico's modern history as it resulted in the massive student massacre on the night of October 2, 1968. The event took place at the "Plaza De Las Tres Culturas" in Tlatelolco, Mexico City and it happened just 10 days before the opening ceremony of the 1968 Summer Olympic Games. At the time it was said that the government used force only as defense from the protesters when they started shooting at them, but records that were release in 2000 suggest that these snipers were under Mexican government orders. The death toll is not known exactly but it ranges from 30 up to 300 with over 1,300 people arrested according to the Center for Research And National Security.

In 1968, all eyes were on Mexico as they were the host country for the Summer Olympics. During this time a revolution was also starting with civilians feeling suppressed of independent labor union and the struggling economy despite the government investing over $150 million in preparations for the Olympics. The National Strike Council organized a protest during that summer and it was formed by students from 70 universities and prep school around Mexico. What the council demanded was the repeal of Articles 145 and 145b of the Penal Code, which sanctioned imprisonment of anyone attending meetings of three or more people, the abolition of granaderos (riot police), freedom to political prisoners and the dismissal of the Chief of police.

On July 23, 1968, the police attached Vocational School #5 claiming the capture of street gangs that had enrolled in that school. Granaderos were used to suppress student demonstrations and ended up assaulting students and teachers along the way. The council then started distributing leaflets and boarding busses to make the general public aware of what the police and government were doing, On August 1 of the same year, Record Barros Sierra of UNAM led 50,000 students in a peaceful protest to show that they were not rabble-rousers and the march had no major disturbances. CNH council issued a paid announcement in the newspaper "El Día" which invited workers, farmers, students, teachers and the general public to participate in a new march. Diaz Ordaz, the President of Mexico, ordered the army to occupy the UNAM campus and students were arrested and beaten indiscriminately and forced Barros Sierra to resign as protest.

On October 2, around 10,000 university and prep school students gathered at the "Plaza De Las Tres Culturas" to protest the government's actions in a peaceful demonstration. One of the biggest chants heard that day were "¡No Queremos Olimpiadas, Queremos Revolución!" ("We Don't Want Olympics, We Want A Revolution!"). Military presence was increasing in the area, with two helicopters over the plaza, yet rally organizers did not attempt to call off the protest. Red flares shot from a nearby area and about twenty minutes later, two more were fired from one of the helicopters. Who attacked who first, remains unclear, as the army claims they were only responding to an attack, while protestors say that firing from the nearby apartment complex was from military after receiving the orders from the helicopter up above.

The plaza then turned into chaos with everyone running in all directions and shots fired. The assault left hundreds dead and many more wounded as the soldiers not only fired at the protestors but innocent bystanders like children and journalists. The mass massacre continued throughout the night with soldiers going house-to-house in the apartment buildings close to the plaxa with electricity and phone lines cut off. Witnesses to the event claim that bodies were piled up and loeaded into military trucks or garbage trucks and sent to unknown destinations.

At the time, the government said the incident was provoked by the demonstrators and the army was only responding to the fire fight that they had started, which the media picked. In 2001, concealed documents revealed that the snipers were members of the Presidential Guard who were instructed to fire to provoke them. "Thousands of students gathered in the square and, as you say, the government version is that the students opened fire. Well, there's been pretty clear evidence now that there was a unit that was called the Brigada Olympica, or the Olympic Brigade, that was made up of special forces of the presidential guard, who opened fire from the buildings that surrounded the square, and that that was the thing that provoked the massacre," Kate Doyle uncovered.