South Africa's former leader Nelson Mandela has been admitted to a hospital in Pretoria for tests, but there is "no cause for alarm," President Jacob Zuma said Saturday. Mandela "is doing well," Zuma said in a statement. "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." Mandela, 94, will receive medical attention "from time to time, which is consistent with his age," Zuma was quoted as saying by CNN. Mandela, a Nobel laureate, spent 27 years in prison for fighting against racial segregation in South Africa. He was elected president in 1994, four years after he was freed from prison.