Mexico City (AFP) - The office of the UN human rights chief voiced concern on Tuesday over claims by foreign experts that Mexico's government stonewalled its investigation of the disappearance of 43 students.
The spokesman for Zeid Ra'ad Al-Hussein, the UN High Commissioner for Human Rights, called on President Enrique Pena Nieto's government to "fully explore" the new lines of investigation recommended by the experts from the Inter-American Commission on Human Rights.
"We are however concerned about the many challenges and obstacles reported by the experts that may have prevented certain lines of inquiries from being further explored," spokesman Rupert Colville said in a statement, citing the possible roles of the military and other authorities in the case.
The experts issued a scathing report on Sunday criticizing the government's investigation into the disappearance of the 43 young men in the southern city of Iguala on September 26, 2014.
The report accused the government of obstructing their work, preventing them from interviewing jailed suspects or members of a military battalion based in Iguala.
While the report does not implicate soldiers in the disappearance, it said the military monitored the students' movements and that an intelligence officer witnessed a clash between the young men and local police.
Prosecutors say the students were whisked away by municipal officers after they hijacked five buses in Iguala to use them for a future protest.
The officers then delivered the students to a drug gang, which killed them and incinerated their bodies at a garbage dump, prosecutors say.
But the experts maintain that there is no scientific proof that the students were burned at the dump.
They urged the government to pursue another line of investigation, the possibility that the students inadvertently took a bus loaded with heroin.
"We call on the government to ensure effective follow-up to the investigation report and to tackle the broader structural challenges it has exposed," Colville said.
The experts' mission ends on Saturday as the government did not extend their stay, saying they had plenty of time to investigate. The government denies stonewalling them, saying they were given full access to the probe.
The commission now plans to set up a mechanism to ensure the government follows up on the recommendations.
Hundreds of people marched in Mexico City on Tuesday in a protest led by parents of the students, who have criticized the government's investigation.
"The Mexican government has led a murky investigation that, far from providing certainty, has offered uncertainty," said Vidulfo Rosales, a lawyer representing the parents.