Former South African President Nelson Mandela has been admitted to a Johannesburg hospital for what is described as “long-standing abdominal complaint.”

A spokesman for South Africa's ruling party, Keith Khosa, says the 93-year-old anti-apartheid icon is in the hospital for a planned checkup and that surgery is not planned. He said “there is no need to worry.”

President Jacob Zuma expressed get-well wishes from the South African people and also requested the public respect the privacy of Mr. Mandela and his family.

Mr. Mandela, winner of the Nobel Peace Prize in 1993, has not appeared in public in recent months due to his fragile health.

Nelson Mandela was imprisoned for 27 years until he was freed in 1990. Four years later he became South Africa's first black president and the country's era of apartheid – all-white rule – ended.