sentences:  In a relatively low-level conflict in late July 1968 between young people in Mexico City, the "Granadero" riot police used violence to tamp down the incident.However, the crackdown had the opposite effect, with students at the National University (UNAM) and the National Polytechnic Institute (IPN) putting aside their traditional rivalries and joining together in protest in the Mexican Student Movement.They protested lack of democracy and social justice in Mexico.