The Nelson Mandela Foundation said Zenani Mandela died in a one-car accident and no one else was injured.[break]
Tummi Shai, a police spokeswoman, told The Associated Press that a case of probable homicide — not unusual in traffic accidents where negligence is suspected — had been opened. Shai would not give any further detail, including the location of the accident.
Thursday´s World Cup concert had drawn tens of thousands of people to Soweto, and traffic was congested into the early hours Friday.
Zenani, who celebrated her 13th birthday on Wednesday, was one of the anti-apartheid icon´s nine great-grandchildren.
"The family has asked for privacy as they mourn this tragedy," the foundation said in a statement.
Mandela, who turns 92 on July 18, has largely retired from public life although as of Thursday it had been anticipated he would make a brief appearance at the World Cup opening ceremony Friday, depending on his health and the weather conditions.
In a statement Thursday, the Foundation said it had been "inundated with requests for meetings, and it will be impossible for Mr. Mandela to accede to even a small fraction of these."
But Mandela met this week with members of the Black Eyed Peas, one of the main acts at Thursday´s concert, and Portugal captain Cristiano Ronaldo and coach Carlos Queiroz — the latter a former coach of South Africa.
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