A mural in Mexico City, blackened with the signatures of some 3400 people, stands as a tribute to the 43 student teachers who were abducted and feared murdered more than two months ago.

Through their "if you sign it wont be forgotten" campaign, Amnesty International obtained more than 120,000 signatures from around the world to demand justice for the missing students.

Executive Director, Perseo Quiroz.

(SOUNDBITE) (Spanish) EXECUTIVE DIRECTOR OF AMNESTY INTERNATIONAL MEXICO, PERSEO QUIROZ, SAYING:

"Jail for the masterminds (is not enough). We have to investigate all the links there could be. All the public servants who by action or omission, are responsible for this unfortunate event as well as the other disappearances there have been in this country."

Authorities have confirmed the identity of at least one of the missing teachers. A government investigation into the case says the teachers were abducted by corrupt police in the southern state of Iguala, th