Rappers Calle 13 showed their support for a group of students missing in Mexico by inviting their parents onstage to address the crowd during the duo's concert in the country on Saturday (22Nov14).

The Puerto Rican group was forbidden by law to speak against Mexican politics during their concert as they are not citizens of the country, frustrating their plans to discuss the 43 students of the Ayotzinapa Teacher Training College who vanished in September (14).

The students were confronted by local police in the city of Iguala as they headed to a protest against the government, and they have not been seen since, amid reports they were murdered by a crime syndicate.

MC Rene Perez planned to speak out about the incident during a concert in Mexico City on Saturday, and to skirt the ban he let some of the parents of the missing students take to the stage instead.

Perez told the crowd, "When there are injustices like the one in Mexico, which go further beyond politics and human rights, I did what I have to do... I met with a father and a mother of a missing student and the story of their sons was very moving; since I recently became a father it was heartbreaking, I support these causes because I can't avoid doing it, it is my duty.

"For me it is impossible to be on a stage and not mentioning these situations in Latin-America... I will not speak tonight at the stage, the Mexicans will."

Following the parents' impassioned speeches, the audience applauded and joined together shouting, "You are not alone."

At the Latin Grammy Awards in Las Vegas on Thursday (20Nov14), Perez was seen wearing a shirt emblazoned with the message, "Ayotzinapa Faltan 43", which translates to "There are 43 missing".