Former South African President Nelson Mandela has been re-admitted to hospital with a recurrence of a lung infection.

A statement from the South African presidency said Mr Mandela, 94, had been admitted just before midnight.

Mr Mandela spent 18 days in hospital in December undergoing treatment for a lung infection and gallstones.

He is widely regarded as the father of the nation for leading the struggle against apartheid.

Mr Mandela served as South Africa's first black president from 1994 to 1999. However, his health has caused concern for some time.

A presidential spokesman told the BBC that Mr Mandela was conscious and was receiving the best possible medical treatment.

"I think we need to be clear that the doctors are attending to Madiba [Mr Mandela] on a continuous basis," spokesman Mac Maharaj said.

"They prefer to act on the side of caution, and the moment they felt there was a recurrence of the lung infection, they felt that it warranted immediate hospitalisation given his age and given his history."

However, the BBC's Andrew Harding in South Africa says the abrupt nature of Mr Mandela's late-night admission is likely to raise concerns.

boron10: The man is old. I don't think he's still enjoying life, the doctors should do him a favour by giving him a Mercy death.

tellwisdom: What happened to Mr Nelson Onwubiko Mandela?? ...You shall not die untimely death sir

nairaman66: As difficult as it it is to say- He's on his last lap.. Seems heaven is calling all our African Icons!

skullbaba: atleast in wont die in a london,india hospital like our yeye leader