Mexican security forces were watching the 43 student teachers who vanished in 2014 both before and during their abduction by criminal forces, according to a new investigation. Evidence turned up by the Interdisciplinary Group of Independent Experts, an independent body probing the infamous Iguala case, has concluded that the state actively concealed evidence that could have helped locate the students, who were taken by corrupt local officials and turned over to a local cartel. The armed forces had intercepted communications that could have been used to track the students, the report found, but officials denied such data existed. The students were being tracked as their school was viewed by the authorities as a nest of potential left-wing dissent, Reuters reported Monday. The panel’s findings poke holes in the previous government’s conclusions on the case—that the students were massacred and incinerated—prompting the current administration to order it reopened. The report stopped short of concluding what had happened to most of the 43 missing, saying that the remains of only two of the students had been positively identified.