Graca Machel, the human rights activist and wife of Nelson Mandela, has warned that South Africa is an “angry nation” teetering on the brink of “something very dangerous” if extreme levels of violence in the country are not addressed. ... Mrs Machel was speaking at the memorial service on Wednesday of Mido Macia, a 27-year-old taxi driver who died in custody after he was tied to the back of a police van and dragged for 500 metres by officers, apparently for arguing over a traffic infringement. The death of Mr Macia came after other recent examples of police brutality, including...