Mexico City, November 24 (teleSUR-RHC)-- Civilians and non-governmental organizations in Mexico found human bones in four more mass graves Sunday, as part of the search efforts to locate the 43 students from the Ayotzinapa Teacher Training College that went missing after being detained by Iguala police on the night of September 26th.

Since that date, more than 15 mass graves and dozens of bodies have been found. However, none of the remains found so far have been linked to the missing students.

The most recent mass graves were found in La Laguna, just west of Iguala, the place where federal authorities say police officers shot at several buses that were transporting the students, killing three of them along with another three civilians, before handing over the survivors to a local gang.

The alarming unearthing of numerous mass graves has raised considerable criticism towards local and federal authorities, who despite more than 50 days having passed since the students disappeared, cannot yet provide information or evidence on their fate.

The situation has sparked outrage and protests across Mexico, with a significant portion of the society distrusting the Attorney General’s assertion that the students were killed and burned in a garbage dump.

Students and activists also accused the federal government of actions aimed at intimidating people against supporting protests in solidarity with the Ayotzinapa case. Many protesters say the disappearance of the students is a state crime and are demanding the resignation of Mexican President Enrique Peña Nieto.