Slideshow: Nelson Mandela: A revolutionary's life

View images of civil rights leader Nelson Mandela, who went from anti-apartheid activist to prisoner to South Africa's first black president.

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Former South African President Nelson Mandela has successfully undergone surgery to have gallstones removed, the office of the presidency said in a statement Saturday.

Mandela, 94, was admitted to hospital last week for a recurring lung infection. Doctors discovered that he had developed gallstones but postponed surgery until his lung infection was treated, the presidency said.

"The procedure was successful and Madiba is recovering," the statement said, referring to Mandela by the clan name used as a sign of affection.

'Who is my Mandela?' South Africans consider icon's place in a changing world

Mandela is revered for being a leader of the struggle against racist white rule in South Africa. He served one five-year term as president before retiring from public life.

The Associated Press contributed to this report.

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