Activist Miguel Angel Jimenez, a leader of social organizations in the violence-ridden southwestern Mexican state of Guerrero was killed yesterday. Jimenez had been heavily involved in the search for the 43 missing Ayotzinapa students, with the investigations being expanded to include finding clandestine graves with bodies of others who have been forcibly disappeared. It is still unclear who was behind Jimenez's murder. Clayton Conn reports from Mexico City. teleSUR