Last November rioters demanded justice for 43 missing college students allegedly abducted by the municipal police in Iguala city in October. In January this year Mexico's government said the missing students had been handed over to a drug cartel by police and then killed and burned to ashes. Many groups questioned this conclusion, saying the government wanted to close the case. This week Argentine forensics team said the attorney general's office made mistakes in 20 genetic profiles collected from student's family members. The government, a mayor, police officers and violent gang members have all been implicated in criminal activities linked to the missing students. No investigation has given plausible evidence to confirm what really happened, or where the missing students or their bodies are.