Argentine folk singer Mercedes Sosa, who fought South America's dictators with her voice and became a giant of contemporary Latin American music, died on Sunday at age 74, her family said in a statement.
Sosa had been in intensive care in a hospital for days with kidney problems. Her body was taken to the Congress building in Buenos Aires for public visitation Sunday afternoon and her remains were to be cremated on Monday, local media reported.
Known affectionately as La Negra -- 'the Black One' due to her dark hair and skin -- Sosa was dubbed "the voice of the silent majority" for championing the poor and fighting for political freedom.
Her version of Violeta Parra's "Gracias a la Vida" ("Thanks to Life") became an anthem for leftists around the world in the 1970s and 1980s when she was forced into exile and her recordings were banned.
"Her undisputed talent, her honesty and her profound convictions leave a great legacy to future generations," her family said in the statement posted on her Web site.
The breadth of her powerful voice earned her plaudits abroad and popularity at home and she cut a striking figure with her long hair and trademark ponchos at live shows into her 70s.
In the turbulent 1960s and 1970s Sosa was a key exponent of the highly politicized Nuevo Cancionero (New Song) movement, which sought to take folk music back to its roots.
She also was a member of the Communist Party and her political sympathies attracted attention from the authorities during Argentina's bloody 1976-83 dictatorship, when up to 30,000 people were killed in a crackdown on leftist dissent.
State censors banned her songs and she fled to Europe in 1979 after being arrested in the middle of a concert along with the entire audience in the university city of La Plata.
She frequently asserted herself as a woman of the left but maintained that her only true vocation was singing.
"Really, I was born to sing," she said in a magazine interview in 2005. "My life is dedicated to singing, finding songs and singing them.
"If I get myself involved in politics, I'd have to neglect what's most important to me, the folk song."
Sosa hailed from a working-class family in the poor sugar-growing province of Tucuman, getting her first taste of fame when she won a local radio talent show at the age of 15.
A specialist in interpreting other people's songs, she embraced the poetry of Argentina and Latin America. While she dabbled in rock and tango in later years, her roots were always in folk music.
Several months before the military dictatorship invaded the British-ruled Falkland Islands in 1982, Sosa returned to her homeland to find that her songs had won her a new, younger generation of fans.
At a string of comeback concerts she sang with up-and-coming stars of popular Argentine music, including Leon Gieco and Charly Garcia, and toured extensively in Europe, Brazil and the United States. She received a 10-minute standing ovation during a performance at New York's Carnegie Hall.
Sosa continued singing up until this year and remained hugely popular, outselling popular teen artists and reggaeton singers in the top charts.
Her last album, "Cantora 1 and 2," a collaboration with Shakira, Caetano Veloso, Jorge Drexler and other artists, was one of the top 10 best selling albums of the year, and she has been nominated for several Latin Grammys this year. The winners will be announced in November.
During her career, Sosa received a string of international accolades that recognized her defense of women's rights, including several Latin Grammys and the CIM-UNESCO prize, with judges praising her "great ethical and moral values" and "her constant defense of human rights."
In poor health for several years, Sosa returned to the public stage with a new album in 2005.
"I'm not young or beautiful, but I've got my voice and the soul that comes out in my voice," she said in a newspaper interview in 2001.
(Additional reporting by Vivianne Rodrigues; Editing by Bill Trott and Paul Simao)