MEXICO CITY: An Austrian laboratory has not found evidence that can confirm that remains found in a trash dump in the southern Mexican state of Guerrero belong to 43 students who disappeared in September 2014, authorities announced.

The Attorney General’s Office said in a statement late Friday night that the Institute of Legal Medicine at the University of Innsbruck examined samples including hair and physical remains.

The office said it was not possible to establish genetic profiles through DNA testing so far, though further testing is still being done with those results to be released in the future.

Mexican investigators have theorised that police handed the students over to drug gang members who killed them and incinerated the bodies at the garbage dump.

That finding has been disputed by two outside groups of experts who examined the case and concluded there was no evidence at the dump of a fire large enough to consume all the bodies. Relatives of the students have also publicly doubted the government investigation.

The Attorney General’s Office said the Austrian lab determined that some of the hair samples were human, while others were of animal origin.

Those found to be human did not yield a match with DNA sequences of family members of the students.

The case of the missing students has attracted national and international condemnation, and the government’s perceived mishandling of it has dogged the administration of President Enrique Pena Nieto.

— AP