Mexico’s attorney general said the government was carrying out DNA tests to confirm the identity of the bodies, a process that he said “will be a challenge” due to the badly burned fragments available to forensic experts.
The remains will then be delivered to the University of Innsbruck for concluding DNA identification.
The task may take some time as even the teeth of victims found at the scene were so badly burned that they virtually turned to dust upon contact.
A total of 43 male students from a teacher training college went missing after clashing with police on September 26th in the town of Iguala.
Suspected gang members have confessed to killing the students, and then setting fire to their bodies.
Relatives of the missing said that they had been told that six bags of human remains had been found along a river near where the students had vanished.
Authorities will continue to consider the students as missing until DNA tests have confirmed their identities.
Felipe de la Cruz, a spokesman for the students' families, has said they will not accept they are dead until it has been officially confirmed by forensic scientists working on the case.
The case has shocked Mexico and there have been large protests over what people say is collusion between officials and organised crime.
The students were protesting against what they said were discriminatory hiring practises and a lack of government spending. Witnesses described seeing the students being bundled into police cars.
Authorities arrested Iguala Mayor Jose Luis Abarca, who is believed to have ordered the abduction of the students, and his wife.
Investigators say the mayor ordered his police chief to prevent the student protest in the city.