Classmates of the 43 students who went missing one month ago in Iguala, in Mexico’s Guerrero state, said Friday that the state governor’s announcement that he is stepping down is not enough — they want to see him “behind bars.”

“We do not care that Governor Ángel Aguirre resigned,” Uriel, a classmate of the missing students who declined to provide his last name for fear reprisals from local police, said during a rally in Guerrero's capital, Chilpancingo. “Our actions will not stop there. We want to see him behind bars.”

Before the rally, thousands marched from the missing students' school, Ayotzinapa Normal School, to Chilpancingo for a Catholic mass. During the march, some students took control of tollbooths along the state's main highway, which leads to the resort town of Acapulco. In previous weeks, student have occupied and burned municipal buildings while protesting the students' disappearance and a perceived lack of action by President Enrique Peña Nieto.

The missing students were protesting government education reforms when local police opened fire on demonstrations, killing three students and three bystanders. After the shootings, local police vehicles drove off with some of the missing students, according to witnesses.

“Police opened fire on us, and it lasted about eight minutes. Those who were able to fled the scene and we were allowed into a nearby home,” Carlos Pérez, a 20-year-old Ayotzinapa student who survived the incident, told Al Jazeera. “Some of us tried to go back. We were completely surrounded and could only escape when the police reloaded.”

“I saw a classmate who wanted to flee, but as he left a bullet hit him and he is now in a vegetative state,” he added.

The Guerrero violence has jolted Mexico, where kidnappings and mass graves have become commonplace since former President Felipe Calderón launched an assault on the country’s warring criminal organizations in 2007. Thousands have marched in Guerrero and other Mexican cities since the students disappeared.