Following a day of mass protests to demand the safe return of the missing Ayotzinapa students, Federal Attorney General Jesus Murillo Karam held a press conference in which he offered an extensive explanation of the government's claim that the students were executed, incinerated, and their remains scattered in a river, by the Guerreros Unidos organized crime gang. To back up his argument, Murillo presented videos of detailed confessions of detained suspects. Clayton Conn reports from Mexico City. teleSUR