Officials tell families of the students about the arrest after a week of protests . Families deny official accounts and deny proof . Federal authorities say they heard confessions from drug traffickers indicating that the college students were rounded up on the orders of the Iguala mayor and then delivered to the drug gang to be murdered . Cesar Nava Gonzalez had been on the run since the students disappeared , they say . Nava allegedly helped round up the 43 students and turn them over to a drug gang .
Officials tell families of the students about the arrest after a week of protests . Families deny official accounts and deny proof . Cesar Nava Gonzalez had been on the run since the students disappeared , they say . Nava allegedly helped round up the 43 students and turn them over to a drug gang .