Relatives of the 43 missing students of the Ayotzinapa Rural Teachers' College arrive to the Palacio Nacional, seat of the Mexican federal executive, for a meeting with Mexican President Andres Manuel Lopez Obrador, in Mexico City, on March 5, 2020. (ALFREDO ESTRELLA / AFP)

MEXICO CITY - Investigators have found a bone fragment belonging to one of 43 students who disappeared in Mexico in September 2014, prosecutors said on Tuesday, only the second set of remains to be definitively identified in a case that roiled the country.

The abduction and apparent massacre of 43 student teachers from the Ayotzinapa Rural Teachers’ College became a symbol of Mexico’s chronic failure to tackle gang violence and corruption

The abduction and apparent massacre of 43 student teachers from the Ayotzinapa Rural Teachers’ College became a symbol of Mexico’s chronic failure to tackle gang violence and corruption.

When President Andres Manuel Lopez Obrador took office 19 months ago, he pledged to shed light on the crime after the last government’s conclusions about the case were widely criticized.

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Prosecutors announced the discovery of the bone remnant of Christian Alfonso Rodriguez Telumbre, who was 19 when he disappeared, as they again questioned central parts of the previous official story.

Omar Gomez, the federal prosecutor who has overseen a fresh probe in the case, said investigators from Austria’s University of Innsbruck identified the bone, which was among remains found in the Cocula municipality of Guerrero state last November.

“This is a new era that breaks with the false narrative which shut down more possibilities to search and to find,” Gomez told reporters. “More than five years after the incident, human remains belonging to one of the victims have been identified.”

After their abduction by corrupt police in the city of Iguala, the students were killed and incinerated by gang members at a waste dump in Cocula, according to the original account.

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But the fragment, whose identification was confirmed by an Argentine forensic team, was not found at the Cocula dump, Gomez said. The search yielded over 100 bone pieces, but only a few were viable for DNA testing, the forensic team said.

In late 2014, Mexico announced it had identified the remains of one of the students, Alexander Mora. Subsequent evidence of a second student was never definitively confirmed.