Tens of thousands of people took to the streets of Mexico City on Wednesday to protest over the disappearance of 43 missing trainee teachers.

The students disappeared from the town of Iguala in Guerrero state nearly six weeks ago after a confrontation with police. Authorities say many of the students were abducted by police and are feared dead.

The demonstrators are demanding answers about their fate.

(SOUNDBITE) (Spanish) PROTESTER, MIRIAM PEREZ, SAYING:

"That there be justice for them (students) and that they (authorities) give more opportunities to young people in universities. And that the bodies be found, whatever the way. If they're aren't alive then at least find them so they (family) can mourn their youth."

The protests have spread beyond Mexico. Demonstrators in Buenos Aires, Argentina gathered outside the Mexican embassy and delivered a petition to officials there.

(SOUNDBITE) (Spanish) PROTESTER, JULIAN ASINER, SAYING:

"The petition