Protests over the 43 student teachers missing in Mexico are refusing to go away.<br /> <br />December 26th was the three-month anniversary since they vanished in Guerrero state.<br /> <br />These demonstrators in Iguala city, from where the students disappeared, vented their anger on a local army base.<br /> <br />The students went missing on September 26 after confrontations with police in Iguala, in southern Guerrero state, that killed three students and three bystanders.<br /> <br />Authorities say they were abducted and massacred by a drugs gang.<br /> <br />Investigators searching for them have uncovered mass graves but the remains of just one of the missing students.<br /> <br />Many believe they're still alive somewhere.<br /> <br />The sister of one of the missing students was among the protesters.<br /> <br />(SOUNDBITE)(Spanish) GUADALUPE SANCHEZ, SISTER OF MISSING STUDENT, SAYING:<br /> <br />"It's been three months, three months without being able to sleep, eat, rest. My mother's exhausted. I ask the government to have some
