Protesters stormed the prosecutor's office of the southern Mexico state of Guerrero on Monday to protest the handling of the disappearance of 43 students, days before the case's first anniversary.
Students, parents of the young men and other protesters demonstrated at the building in the state capital Chilpancingo and placed pictures of the missing on the windows.
A group of protesters entered the offices, breaking computers and surveillance cameras and causing damage to four vehicles.
Vidulfo Rosales, an attorney for the relatives of the 43 missing students, said the protest was held to press the government find the young men, "which is the movement's main demand."
On Saturday, a protest is expected in Mexico City to mark one year since the students disappeared after they were attacked by local police in the Guerrero town of Iguala on the night of September 26-27.
Prosecutors say the officers delivered the students to the Guerreros Unidos drug gang, which killed them and incinerated their bodies after confusing them with rivals.
Earlier this month, independent investigators contradicted those official conclusions, saying there was no evidence that the young men were burned in a garbage dump.
Parents of the students plan to begin a 48-hour hunger strike in Mexico City on Wednesday, a day before meeting with President Enrique Pena Nieto, whose approval ratings have plummeted over his government's handling of the case.