Around 60 people were hurt and more than 100 arrested Monday when Mexican federal police stormed three schools in the western state of Michoacan where students were holding dozens of commandeered vehicles, authorities said.
While state interior minister Jesus Reyna Garcia told reporters that 120 students were taken into custody, unofficial accounts put the figure at more than 300.
The injured include both police and students, paramedics said.
Launched in the pre-dawn hours, the police operation was aimed at recovering the more than 50 buses and delivery trucks seized on Oct. 4 and taken to three normal schools in an area of Michoacan populated by Purepecha Indians.
Students took the vehicles as part of protests against changes to the curriculum at Mexico's normal schools. Those institutions - once common in both Europe and the Americas - prepare young people for careers in teaching.
The nearly simultaneous raids came a day before Mexico's outgoing president, Felipe Calderon, is expected to visit several towns in his native Michoacan, including Cheran, the site of one of the school involved in the protest.
Police were supported up by U.S.-supplied Black Hawk helicopters, fire trucks and ambulances.
Patrol cars were among several vehicles set on fire during Monday's confrontations. In Cheran, parents of the protesting students and other Purepecha residents retained control of the school and seized additional buses to force authorities to release the young detainees.
Students at the normal school in Arteaga reached an agreement with police to hand over the facility and the commandeered vehicles.
The union representing most of Michoacan's teachers, the CNTE, denounced Monday's police operation and shut down the state's public primary and middle schools.
Union members also blocked the road linking Cheran with Morelia, the state capital. EFE