Río Piedras Massacre (1935)

On October 24, 1935, a caravan of Nationalist Party members was intercepted by police near the University of Puerto Rico campus in Río Piedras. Police opened fire on the vehicle, killing four Nationalists — Ramón S. Pagán, José Santiago Barea, Pedro Quiñones, and Eduardo Rodríguez Vega — and an innocent bystander.

Context:
The massacre occurred during a period of intense repression of the Nationalist movement under U.S.-appointed Governor Blanton Winship. The colonial police, under Chief E. Francis Riggs, had been conducting an aggressive campaign against Pedro Albizu Campos and the Nationalist Party.

Consequences:
- The killings galvanized support for the Nationalist movement
- They set in motion a chain of events: on February 23, 1936, two young Nationalists — Hiram Rosado and Elías Beauchamp — shot and killed Police Chief Riggs in retaliation for the Río Piedras massacre
- Rosado and Beauchamp were taken to police headquarters and murdered without trial — extra-judicially executed
- The Riggs assassination gave U.S. authorities the pretext to arrest Albizu Campos, who was convicted of 'seditious conspiracy' and imprisoned for 10 years
- The removal of Albizu Campos from leadership temporarily weakened the Nationalist Party

Pattern of Violence:
The Río Piedras Massacre was part of a systematic campaign of colonial violence against the independence movement during the 1930s:
- Río Piedras Massacre (1935): 5 killed
- Murder of Rosado and Beauchamp (1936): 2 extra-judicially executed
- Ponce Massacre (1937): 19 killed, 200+ wounded
- Arrest and imprisonment of Albizu Campos (1937)

These events demonstrate that the colonial government used lethal force to suppress the independence movement — and then used the movement's response to justify further repression.