In Mexico City, President-elect Andrés Manuel López Obrador welcomed the head of the International Olympic Committee Thursday to a celebration of the 50th anniversary of the 1968 Olympic Games, held in Mexico’s capital city. The ceremony came just days after Mexico’s government acknowledged for the first time that the state was criminally responsible for the massacre of hundreds of student protesters in Mexico City on the eve of the '68 Olympics. To date, no one has been convicted over what's known as the Tlatelolco massacre. Interior Ministry official Jaime Rochin said Monday, “The use of sniper fire was a state crime, aimed at creating chaos, terror and an official narrative to criminalize the protest. It was a state crime that continued beyond October 2nd with arbitrary arrests and torture.”