Local authorities in Guerrero tend to be wary of student protests because of suspected ties with leftist guerrillas or rival political groups.[18] In 1995, the Guerrero state police killed seventeen farmers and injured twenty-one others during a protest in an event known as the Aguas Blancas massacre. The massacre led to the creation of the Popular Revolutionary Army (Spanish: Ejrcito Popular Revolucionario), which is believed by some state officials to retain some political influence in Guerrero.[21] Students claim to have no ties with such groups, and that the only thing they have in common with them is socialist ideology.[18] In addition, in Guerrero, where the bus companies are assumed to pay protection money, student campaigns are seen as threatening to organized crime.[19]