MEXICO CITY (AP) — Raul Alvarez Garin, a leader in the 1968 student uprising that culminated in the massacre of protesters in Mexico City, has died at age 73.

Alvarez Garin died Friday in the capital after a yearlong battle with cancer, according to a Facebook statement posted by the Committee of the ’68 Pro Democratic Liberties. He founded the group to demand punishment for those responsible for the massacre.

Alvarez Garin, a university professor, was one of the most recognized leaders of Mexico’s leftist student movement that was deflated when soldiers opened fire on protesters at Tlatelolco Plaza on Oct. 2, 1968. An unknown number of people were killed.

After being imprisoned for nearly three years, Alvarez Garin continued to work for leftist causes and was a founder of the Democratic Revolution Party.

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