Mexican authorities believe that 43 students who disappeared four months ago were all killed by members of a drug cartel who believed that they had been infiltrated by a rival gang, the country’s attorney general said on Tuesday.

Jesús Murillo said that investigators had established that the bodies of the murdered students were incinerated at a rubbish tip by members of the Guerreros Unidos drug gang who believed the students were part of an attempt to take over their territory by a group known as Los Rojos backed by corrupt local authorities.





“The evidence allows us to determine that the students were kidnapped, killed, burned and thrown into the river,” Murillo told a press conference on Tuesday. “This is the historical truth of what happened.”

The students disappeared in Iguala on the night of 26 September, after the convoy of buses they were travelling on came under attack by municipal police.

The case has triggered a wave of fury around Mexico with protesters accusing the government of failing to do enough to find the students alive, and questioning the quality of the investigation. Demonstrators marked the four-month anniversary of the disappearance with a march in Mexico City.

According to the investigation, the police rounded up the missing students during the attacks, and then handed them over to members of Guerreros Unidos. The gang members then allegedly took the students to a rubbish tip outside the nearby town of Cocula where they killed those who arrived alive, and burned them all on a huge pyre of tyres soaked in diesel fuel that raged for 12 hours.

Murillo first revealed the existence of the alleged fire in November, citing confessions of arrested Guerreros Unidos members. He said these had also led the authorities to find plastic bags filled with ashes and badly burned bone fragments and teeth dumped in a nearby river.

Scientists at the University of Innsbruck in Austria succeeded in matching DNA extracted from one bone fragment with samples taken from one of the missing students, but the laboratory said last week that further matches would be impossible because “excessive heat” had made it impossible to retrieve any further DNA from the remains.

Parents of the missing students have repeatedly questioned the official version. They have accused the government of trying to close the case without properly exploring the possibility that their children could still be alive.

A group of Mexican scientists have also insisted that there is insufficient evidence in the Cocula tip of a fire of the proportions required to reduce so many bodies to so little.

“What the government wants to do is close the case,” Epifanio Alvarez, the father of one of the missing, told a press conference on Tuesday night at which the parents vowed to continue their struggle to find their children alive.

“We cannot accept any of what was said because we do not have enough evidence … The government has stamped on our dignity and destroyed us.”

Vidulfo Rosales, the human rights lawyer who represents the parents, listed objections to the apparent closure of the investigation. These included skepticism over the quality of the scientific evidence presented by Murillo, as well as suspicions that the detainee confessions were obtained through torture. He also highlighted the fact that, so far, only one missing student has been matched to bone fragments, which leaves 42 still missing.

Rosales also insisted on the need to also investigate the possible role of the army in the events, which has been repeatedly ruled out by the attorney general. The lawyer said it was also necessary to broaden the investigation into the corruption that protected the Guerreros Unidos cartel in the Iguala area beyond the municipal authorities.

Earlier, Murillo spoke to dispel lingering skepticism by insisting that tests had revealed that rocks, teeth and the remains of tyres found at the site were subjected to temperatures of up to 1500C. Murillo also said there was “unquestionable evidence” that the remains found in the river came from the tip.

“It is completely clear,” he said. “Except to those who don’t want to believe it.”

Relatives did not appear convinced.

“They could have been planted,” Valentín González, brother-in-law of missing student Abel García, told the Associated Press. “So the parents are now more prepared than ever to look [for the students] alive.”

Tuesday’s press conference was also the first time Murillo has said that the students were disappeared because Guerreros Unidos members believed their group included members of the Los Rojos cartel. He said confusion had been fuelled by the fact that the students had shaven heads, apparently also a characteristic of Los Rojos.

He presented recordings of confessions by the alleged participants in the massacre saying they were responding to an attempted incursion by Los Rojos.

“We haven’t found evidence that there were any Rojos [among the students],” Murillo said. “But it is what [the Guerreros Unidos] thought.”