Mexico's missing students: Yet another mass grave uncovered

© AFP Photo / Jesus Guerrero

Forensic personnel arrive at the scene where a new mass grave has been discovered in a trash dump on the outskirts of Cocula, Guerrero state, Mexico on October 27, 2014.

A new mass grave was uncovered in the same Mexican state as the one found after the September 26 disappearance of 43 students at a protest. The police were led to the site by four arrested gang members.

The news of a suspected fresh grave was shared with local press by a police official not authorized to share details of the new find.

Although Attorney General Jesus Murillo Karam announced Monday's arrests at a press conference, news of the fresh mass grave hadn't been made official.

Those arrested are thought to belong to the Guerreros Unidos - the gang connected to the initial disappearances and believed to have ties with the highest echelons of the police force.

According to Murillo Karam, two of the gangsters claimed to have come into contact with a large group of people around the time of the September disappearance. This information is currently being confirmed.

The newly discovered grave site is in the town of Cocula, about 17 kilometers (10 miles) from the site of the September rights' protests, where the students were last seen.

Shortly before the Monday arrests and the associated find, investigators also uncovered 11 graves containing 38 sets of human remains, also in the municipality of Iguala. But DNA testing for the missing students came back negative.

The number of people detained in the case now stands at 56. The prosecution is convinced the mayor of Iguala, Jose Luis Abarca and his wife Maria de los Angeles Pineda, are "possible masterminds" in the attack. Earlier, arrested members of the Guerreros had told police that Pineda was their inside woman in the government. She is known to come from a long line of prominent drug traffickers.

The two are being sought by police after the mayor quitted his post following the protests, and never reappeared.

Fresh information provided to the police says the abducted students had originally been handed to police, before being taken to Cocula. They were also allegedly loaded onto a dump truck, before being taken to Iguala, still alive, according to a testimony from the detained Guerreros.

The initial September incident saw student teachers from a local college clash with police during a protest over rights, which led to at least six deaths.

The ensuing chaos and protests (which spread to other cities) have sent shockwaves through a country already struggling with some of the highest kidnapping and murder rates in the world.

Local forensics working in Guerrero told the local El Universal that a total of 152 bodies have been recovered from mass graves in the state since the start of 2014.

In several states, including the capital Mexico City, thousands have since taken to the streets - some, to march peacefully, with others staging assaults on government buildings, breaking glass and throwing Molotov Cocktails and rocks.

Mexico is the second biggest economy in Latin America. This latest police corruption scandal is a serious blow to President Enrique Pena Nieto's attempts to present it in a different light. His predecessor's term saw 100,000 people being 'disappeared' and dying from 2007.