Warning: This video has disturbing images, and documents the deaths of seventeen peasants at the hands of the police.
The original video has apparently been taken down from YouTube, but see below for other versions.
Here is a version that can only be viewed on YouTube (as it is age-restricted): LA MATANZA DE AGUAS BLANCAS (28-JUN-1995)… ACTO DE VIOLENCIA Y DE IMPUNIDAD DEL PRI GOBIERNO…
From the YouTube description:
“Testimonio en video de la matanza ocurrida el 25 de junio de 1995 en el vado de Aguas Blancas, Guerrero, por fuerzas de la ley en contra de ciudadanos simpatizantes de la Organización Campesina de la Sierra del Sur. En los últimos 8 meses de la administración del gobernador Figueroa se reportaron 10 asesinatos colectivos con la participación de la entonces temida Policía Judicial del Estado. Aguas Blancas es el único documentado de esta manera.”
La masacre de Aguas Blancas 1997.flv:
This is a longer version, which also has commentary and interviews.
And the above is all in Spanish, but here is an English-language documentary about another (similar, but different) killing in Mexico, the murder of 43 students from a college in Ayotzinapa in 2014.
The Missing 43: Mexico’s Disappeared Students (Full Length):