Mexico City - A second independent forensic investigation rejected on Tuesday the Mexican government's conclusion that 43 students who went missing in 2014 were incinerated at a garbage dump.
The Argentine Forensic Anthropology Team said there was "no consistency between the physical evidence" and the testimony of drug gang suspects who claimed that the students were killed and burned at the site.
While charred bone remains of at least 19 people were found at the dump in Cocula, southern Guerrero state, they "clearly do not belong" to the trainee teachers, said Miguel Nieva, a member of the Argentine team.
Nieva showed photos and studies of plants demonstrating that there was "not any sign of a recent fire in the vegetation" at the dump in Cocula, southern Guerrero state.
Nieva said there were several blazes at the landfill over the years since 2010, but "no fire occurred on the night of" September 26 to 27, 2014, when the students vanished after they were detained by police in the nearby town of Iguala.
Former attorney general Jesus Murillo Karam declared last year that the "historic truth" was that the students were delivered to a drug cartel, which killed them, incinerated their bodies at the dump and tossed the remains in a river.
One of the students was identified among the remains found in bags in the river. Authorities also found a possible DNA match for a second student.
But the Argentines, who have participated in the investigations at the request of the students' families, expressed doubts about the origin of the remains.
The group said it was not present when the bags were found, so they cannot be sure of the remains' origins.
The bone that allowed an Austrian lab to identify the student, Alexander Mora, was "unusual of its size compared to the other fragments in the same bag" and had minimal exposure to fire, said Argentine team member Mercedes Doretti.
Independent investigators from the Inter-American Commission on Human Rights rejected the official conclusions in September, saying a fire expert found no scientific evidence of a massive funeral pyre at the dump.
Attorney General Arely Gomez has vowed to conduct a new forensic investigation with international experts while looking at other lines of investigation into the students' possible final destination.
Her office said that it had received the Argentine team's report and that it would be reviewed.
The statement said the case was not closed and that authorities are finalizing the team to conduct a new analysis of the fire claims in the tragedy that has triggered international outrage and haunted the administration of President Enrique Pena Nieto.
Nwe York-based Human Rights Watch said the Argentine team's report shows that the initial conclusions in the case were "no more than fiction."
"What Mexico needs isn't just an investigation into the whereabouts of the disappeared students, but also an investigation of the authorities who produced the unsubstantiated official version of events, including the former attorney general Jesus Murillo Karam," said the group's Americas director, Jose Miguel Vivanco.