MEXICO CITY — Mexico will open a new investigation into the 2014 disappearance and apparent massacre of 43 students, authorities said on Wednesday (Sept 18), a controversial case that caused a crisis for the previous government and drew international criticism.

"We're going to start again," Omar Gomez, a special prosecutor appointed to oversee the reexamination of the case, said in a statement.

The alleged abduction and suspected massacre of the 43 student teachers in the southwestern city of Iguala by corrupt police working with a violent drug gang precipitated one of the worst crises of former President Enrique Pena Nieto's government.

His successor Andres Manuel Lopez Obrador set up a commission late last year to look into the handling of the case, and has since periodically announced developments, including an investigation into the officials who led the investigation.

Gomez on Wednesday said authorities would investigate "a long list of politicians that bear different degrees of responsibilities."

Felipe de la Cruz, father of one of the missing students, welcomed the official reopening of the case.

"Unfortunately it has been five years of feeding lies, we practically prefer to start from scratch because at first everything was done badly," Mr de la Cruz said in an interview.

The government has said its investigation into former officials from the Pena Nieto administration for their handling of the probe will target a former attorney general and his top aides.

Mr Lopez Obrador has also criticised the release from prison of several suspects in the case, after a judge ordered the release of a key suspect. He told relatives of the victims in a private meeting earlier this week that he was working on preventing the release of any more. So far 77 of 142 suspects detained have been released by courts.

The official account of the incident released by the previous government stated the students were killed and then incinerated by gang members after their abduction. Investigators have only definitively identified the remains of one of the 43.

The UN human rights office said in a report last year that Mexican authorities had probably tortured dozens of people during the investigation. REUTERS