JOHANNESBURG - Former South African President Nelson Mandela is undergoing specialised tests in hospital and there is no reason to panic, Deputy President Kgalema Motlanthe said in a statement on Friday.

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A source close to Mandela told Reuters on Thursday the 92-year-old anti-apartheid icon is recovering from a collapsed lung and could be released from hospital as early as Friday.

Motlanthe said Mandela was in good spirits. "Medically there is no need to panic. Dr. Mandela suffers from (an) ailment common to people of his age, and conditions that have developed over years. We may recall that he has suffered from tuberculosis whilst on Robben Island and has had previous respiratory infections.