Johannesburg, Zindzi Mandela, the daughter of South Africa's anti-apartheid icons Nelson Mandela and Winnie Madikizela-Mandela, died here on Monday, according to the country's public broadcaster SABC reported.

She died on Monday morning aged 59, the BBC quoted the SABC as saying citing a family member as saying

Zindzi Mandela was the South African ambassador to Denmark at the time of her death.

The cause of her death was not immediately revealed.

"The 59-year-old daughter of former president Nelson Mandela and struggle stalwart Winnie Madikizela-Mandela, passed away at a Johannesburg hospital in the early hours of this morning," said SABC.

She was Nelson Mandela's sixth child and his second with Winnie Madikizela-Mandela.