Mexico City's landmark Monument to the Revolution in the Plaza de la Republica is illuminated with the names of the 43 students from a rural school on the eve of the 10-year anniversary of their disappearance. The Ayotzinapa students, believed to have been massacred, represent one of Mexico's worst human rights atrocities, in a country where drug violence has left over 100,000 people missing. So far, the remains of only three of the victims have been identified through genetic testing of bone fragments. IMAGES