An independent forensics team rejected the Mexican government's conclusions over the fate of the 43 teachers college students who were disappeared by local police and a drug gang.
The statement published Saturday by the Argentine Forensic Anthropology Team (EAAF) was the strongest and most detailed critical reaction yet from the group, which joined the investigation into the September 26 attacks at the request of the missing Ayotzinapa Normal School students' parents.
Remains of non-student victims were likely found at the dump in the state of Guerrero where the government said the 43 students were incinerated, and DNA samples authorities sent to be studied in Austria did not match a duplicate sample gathered by the EAAF, an "unusual" inconsistency in evidence gathering, the EAAF said.
These two revelations were among seven points the Argentine group said indicated "serious" irregularities in the handling of the case that has thrown the government of President Enrique Peña Nieto into the international spotlight over the issue of forced disappearances.
Murillo Karam's office struck back against the EAAF today, releasing a statement saying the group's assertions "appear to be more speculation than certainties."
On Friday, a group of civilians were kidnapped in Cocula, the same municipality where the dump is located. Mexican soldiers and community police militias by Monday had located and rescued 10 people that local reports identified as employees of a mining company, in a sign of the pervasiveness of kidnapping the state of Guerrero.
The incident so far does not appear related to the missing students.
Mexican attorney general Jesus Murillo Karam has attempted to declare the investigation solved, claiming that the young men were murdered and burned in the Cocula dump as a group, but that their remains will never be fully found or identified.
The new statement from the EAAF pointed out that the ravine used as a trash dump was not secured since at least the day after Murillo Karam announced the incineration theory, despite the fact that the investigation technically remained open.
"The (EAAF) wishes to express that we are not excluding the possibility that some of the normalista students met the fate that was described by the attorney general. At the same time, up until this moment, we have no scientific evidence to confirm that remains of the normalista students exist in the Cocula garbage dump," the statement said.
VICE News travelled to the Cocula dump on November 11. In the vicinity, no government representative, security agent, or member of any forensics team was present.
The Argentina team joined the case on October 4, 2014, after the government agreed to demands of the disappeared students' families, who said they had little faith in government's ability to find their sons.
The EAAF is recognized for its work on cases of forced disappearances in Latin America. The group had already been working in Mexico, investigating the case of the 72 Central and South American migrants massacred in San Fernando, Tamaulipas state, in 2010.
Parents of the missing held a press conference on Monday in which they backed the findings of the EAAF and said they were more convinced than ever that the government's investigation has failed.
"For us it's clear that the 'historical truth' of the government has crumbled," said parent spokesman, Felipe de la Cruz. "We were right from the start to not trust the government's line."
Only one of the missing students, Alexander Mora, has been identified from remains the government said were recovered at the dump or river. But in its earliest refutal of the government's investigation, the EAAF said in December that its members were not present when Mora's bone fragment was supposedly found.
The Saturday statement went further, saying that the group did not observe the work of government divers who authorities said scooped out bags full of human remains from the San Juan river.
The attorney general's statement in response was uncharacteristically blunt and defensive.
The team's report also features satellite images that show that there had been numerous fires in the garbage dump since 2010, and that other human remains may be mixed in with evidence linked to the missing students. The EAAF found dentures among remains recovered at the dump, suggesting non-student victims were killed there, because none of the students had dental fixtures, the group said.
Then, according to the Argentina team, the government extracted more evidence from the site on November 15 — without notifying them.
VICE News travelled to the Cocula dump on November 11. In the vicinity, no government representative, security agent, or member of any forensics team was present. The area was not cordoned off and there was unlimited access to the public.
The attorney general's Monday statement in response was uncharacteristically blunt and defensive.
It said that the EAAF was not invited to observe every step in the criminal investigation because the group was only certified to observe in anthropology, genetics, and criminal forensic work. The response also said that any other hypothesis besides the dump incineration line was "divorced from reality."
But other anomalies in Mexico's case raise alarm, the EAAF said.
According to the group, 20 of the 134 genetic profiles that the Mexican government sent to a lab at the University of Innsbruck in Austria do not match with the profiles that the EAAF sent to the same lab, an anomaly which the group noted very rarely happens. (The government on Monday said that was due to a transcription error.)
One of the EAAF investigators told the Mexican weekly Proceso that the group had not planned on making their announcement on the case so soon.
"The normal procedure would have been for both teams to present our conclusions at the same time at the end of the investigation, but considering what [the attorney general's office] said, we weren't left with another option," the EAAF member said.
Doubts on Mexico's handling of the case have been raised almost across the board among international observers.
Amnesty International called the government's investigation "far from conclusive." Mexico's own National Human Rights Commission declared that its investigators would "exhaust all possible lines of investigation." The Inter-American Commission on Human Rights is also looking into the case.
Even US President Barack Obama said the US government "offered to help" Mexico in its search for the students.
Last week, two parents of missing Ayotzinapa students travelled with Mexican and international human-rights workers to speak before the United Nations Committee on Enforced Disappearances. The committee expressed concern over the case and still many unsolved forced disappearances from the Mexican government's "Dirty War" against rebels and guerrillas in the state of Guerrero.
Follow Andalusia Knoll on Twitter @andalalucha.