Authorities in Mexico announced the arrests of four more drug gang members in last month’s kidnapping and feared massacre of some 43-university students in the southern town of Iguala.  It comes alongside reports that yet another mass grave has been found in the hills around the troubled town.

“Today we now have those who organized the disappearance of these youths,” said Mexico’s Attorney General Jesus Murillo.  The suspects are members of the Guerreros Unidos gang, which is believed to have links to Iguala’s fugitive mayor and his wife.  Mayor Jose Luis Abarca and his wife Maria de los Angeles went on the lam after being named the likely masterminds of the disappearances.  More than 50 people have been arrested in the case so far, including police officers.

The latest mass grave is located in a trash dump near Iguala’s neighboring village Cocula.  It’s about the sixth mass grave uncovered in the search for the missing students.  So far, DNA have not been able to match the bodies found to the students.

It was on 26 September that the students were last seen, being forced into police vans after a raucous anti-corruption demonstration.  The disappearances have triggered massive protests around the country, and are undermining President Enrique Pena Nieto's claims that Mexico is becoming safer under his watch.