Nelson Mandela Suffering From Lung Infection

Dec. 11, 2012— -- Nelson Mandela's recurring lung infection is responding to medical treatments, South Africa's presidential spokesman said today.

The anti-apartheid icon is "receiving appropriate treatment and he is responding to the treatment," Mac Maharaj said early this morning.

Mandela, 94, was admitted to 1 Military Hospital in Pretoria Saturday for routine medical testing, "which is consistent for his age," South African officials said.

The nation's defense minister Monday said that Mandela was undergoing a series of unspecified tests.

"He is doing very, very well," Nosiviwe Mapisa-Nqakula said. "And that it is important for all of us to keep him in our prayers but also to be as calm as is possible and not cause a state of panic in the country."

Click Here to See Photos of Nelson Mandela Through the Years

Government officials had kept a tight lid on releasing specifics regarding Mandela's health status and the specific reason for the latest hospital visit. With little details emerging about Mandela's health, many South Africans have complained about the lack of concrete information disseminated across the country.

Politicians have tried to reassure the people of South Africa that the revered leader is doing well.

"We wish Madiba all the best," South African President Jacob Zuma said in a statement Saturday, using Mandela's Xhosa clan name. "The medical team is assured of our support as they look after and ensure the comfort of our beloved founding President of a free and democratic South Africa."

Zuma visited Mandela Sunday morning and said he "looked well and he can assure us he's in good hands," spokesman Maharaj said.

Mandela was admitted to the hospital in February to receive treatment for a "long-standing abdominal complaint."

Mandela was also admitted to Milpark Hospital in Johannesburg in January 2011 with a respiratory infection. His public appearances have become increasingly rare as he deals with declining health. His last public appearance was in July of 2010, when he attended the final match and closing ceremonies of the World Cup held in South Africa.

He was released from prison in 1990, after serving nearly three decades of hard labor at the infamous Robben Island.

Mandela, who fought to dismantle the country's racist regime, was elected as South Africa's first black president in 1994.

After he left office in 1999, Mandela became a global statesman, mediating conflicts in some of the world's most troubled spots.

Mandela has since retired to his childhood home in Qunu. Occasionally, the government has released photos of the former president after high-profile visitors meet with him in Qunu.

Secretary of State Hillary Clinton was the last U.S. diplomat to meet with Mandela shortly after he celebrated his 94th birthday this summer.

ABC News' Bazi Kanani contributed to this report.