Thousands of supporters of Puerto Rican independence on Monday celebrated the 145th anniversary of the anti-colonial uprising known as the Grito de Lares, an event which this year they dedicated to Oscar Lopez Rivera, who has been in prison in the United States for 32 years.

Starting early in the morning, hundreds of independence-minded supporters gathered at the Plaza de la Revolucion in the town of Lares, while others attended a commemorative Mass in memory of the fleeting insurrection of Sept. 23, 1868.

Defenders of Puerto Rican independence placed floral offerings at the bust of the main figure of the Grito de Lares, Ramon Emeterio Betances.

There, the attendees sang the revolutionary anthem of Puerto Rico and then heard public remarks by several politicians with the Puerto Rican Independence Party.

Lopez Rivera, 70, is considered by some Puerto Ricans to be a U.S. political prisoner, while Washington accuses him of belonging to the National Liberation Armed Forces, a group that in the late 1970s committed acts of sabotage in Chicago and New York to demand independence for the Caribbean island, which is a U.S. commonwealth.

Lopez Rivera was sentenced to 55 years in prison in August 1981 for conspiracy and sedition against the U.S. government and in 1988 he was sentenced to an additional 15 years for conspiring to escape from prison. He is the only one of the 13 imprisoned Puerto Ricans to reject the 1999 release offer made to them by then-President Bill Clinton.

From Lares, the demonstrators marched to Hormigueros, where there was an event to memorialize the independence leader of the clandestine Los Macheteros organization, Filiberto Ojeda, who died on Sept. 23, 2005, at the hands of FBI agents.

Puerto Rico came under Washington's sway in 1898 and island residents were granted U.S. citizenship in 1917, yet they cannot vote in presidential elections, though Puerto Ricans living in the continental United States can.

Since 1952, the island has been a self-governing, unincorporated territory of the United States with broad internal autonomy, but without the right to conduct its own foreign policy. EFE