Singer, anti-apartheid icon Miriam Makeba dies

(CNN) -- Legendary South African singer Miriam Makeba, an outspoken critic of apartheid, died late Sunday in southern Italy, a hospital spokesman has told CNN. She was 76.

Makeba, shown here in Switzerland in 2006, was an outpsoken opponent of apartheid.

The cause of death was not immediately known.

Makeba's career spanned parts of six decades and helped bring African music to a global audience. She was known as the "Empress of African Song" and "Mama Africa."

She was considered by many to be the most important female vocalist to come out of South Africa.

Former South African President Nelson Mandela, a prisoner under the nation's apartheid regime, mourned her death, but praised her commitment to the cause.

"Despite her tremendous sacrifice and the pain she felt to leave behind her beloved family and her country when she went into exile, she continued to make us proud as she used her worldwide fame to focus attention on the abomination of apartheid," Mandela said in a statement released Monday.

An outspoken critic of apartheid, she had her South African citizenship revoked by the country's government in 1960. For the next 30 years, Makeba considered herself a "citizen of the world" until her citizenship was restored.

She recorded her first single, "Lakutshona Llange," in 1953 as a member of the Manhattan Brothers.

Makeba's breakthrough hit in the United States came in 1967, when "Pata Pata" charted. It was recorded 11 years earlier in South Africa.

Makeba lived in exile for 31 years in the United States, France, Guinea in West Africa and Belgium, The Associated Press reported. She returned to South Africa in 1990, when many long-exiled South Africans returned under reforms instituted by then-President F.W. de Klerk.

"I never understood why I couldn't come home," Ms. Makeba said upon her return, according to an AP report. "I never committed any crime."

Makeba spoke before the United Nations in 1976, denouncing the policy of apartheid, or racial segregation, according to AP. After that, South Africa's government-run radio and television refused to broadcast her songs until 1989.

American entertainer Steve Allen helped launch her career in the United States and she often toured with singer Harry Belafonte during the 1960s. In 1987 she performed with singer Paul Simon on his "Graceland" concert tour.

CNN's David Ariosto contributed to this report