The 94-year-old Mandela, his nation's first black president, has had several health scares in recent years that sparked rumors of his death. But this time, the office of President Jacob Zuma reassured South Africans in a statement that there was no cause for alarm for the man they know affectionately as Madiba.
"Former President Mandela will receive medical attention from time to time which is consistent with his age. President Zuma assures all that Madiba is doing well and there is no cause for alarm," the statement said.
The government offered no details of the tests.
Mandela, who is increasingly frail, has moved to the rural village of Qunu in the province of Eastern Cape, not far from his birthplace. He has retired from public life and plays no role in politics, though he remains an important figurehead in the ruling African National Congress.
"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 said in the statement.
In 2011, Mandela had to be hospitalized for a respiratory infection. In February this year he was hospitalized for minor diagnostic surgery related to an abdominal complaint.
Mandela's hospitalization comes after speculation in a South African newspaper that medicine meant for him was aboard a plane that crashed Wednesday in a mountainous region of South Africa on its way from Pretoria to Mthatha, near Qunu.
South African defense officials dismissed the reports.