Mexico said on Sunday that mounting evidence and initial DNA tests confirmed that 43 trainee teachers abducted by corrupt police 10 weeks ago were incinerated at a garbage dump by drug gang members, although forensic experts sounded a note of caution.
Attorney General Jesus Murillo confirmed that one of the students had been identified by experts in Austria from a bone fragment in a bag of ash and bits of burned tire found in a river where drug gang members said they tossed the students' remains.
"This scientific proof confirms that the remains found at the scene coincide with the evidence of the investigation," Murillo said. "We will continue with the probe until all the guilty have been arrested."
However, Argentine forensic experts helping to identify the remains stressed there was still insufficient physical or scientific evidence linking the remains found dumped in a river to the site of the suspected massacre, a garbage dump in Cocula.
"The evidence linking both sites is so far essentially based on witness testimony," the Argentine Forensic Anthropology Team (EAAF) said in a statement, stressing it was not present when the identified remains were found.
"The search for the missing should continue."
President Enrique Pena Nieto is facing his deepest crisis over his government's handling of the probe. The case laid bare Mexico's deep problem of impunity and corruption and it has overshadowed his efforts to focus attention on economic reforms.
Speaking at a conference in Veracruz on Sunday, Pena Nieto sent his condolences to the parents of Alexander Mora, the student whose remains have been identified.
A month ago, Murillo said drug gang members had confessed to murdering the students and burning their bodies in a pyre of tires at an isolated dump.
During the search for the students in the state of Guerrero, dozens more bodies were discovered in mass graves. More than 100,000 people have been killed in Mexico in gang-related violence since 2007.
"There is a lot of rage, but it is not just this case," said political science student Jimena Rodriguez at the Saturday night march. "There are so many missing, and they do not have the least interest in really investigating."
