On September 26, 2014, 43 male students from a teacher college went missing in the Mexican southwestern city of Iguala, State of Guerrero, after protesting discriminatory hiring and funding practices in the city. The students were last seen being forced into police vans after the officers opened fire, killing six.
Lopez is a key figure in a local influential drug gang, to which, according to government investigators, the students were handed over by the police.
Additional evidence, provided by independent experts, allows that local police and army were complicit in the kidnappings. The victims' families and teachers' unions claimed the government was quick to shift the blame to criminal gangs.