Obama hails Mandela as a 'giant of history' at Soweto memorial service
Barack Obama hails freedom icon as leaders, royalty and celebrities from around the globe gather to pay tribute at celebration in Soweto

Tens of thousands of South Africans united in a proud and noisy celebration yesterday at a rain-soaked memorial service to Nelson Mandela.
The emotional event was attended by presidents and royalty and watched by millions around the world.
Songs of praise and revolution, many harking back to the apartheid era that Mandela helped condemn to history, echoed around the giant stadium in Soweto.
Watch: Obama leads world tributes to Mandela at memorial
Despite the profound sense of national sorrow triggered by Mandela's death at the age of 95 last Thursday, the mood was upbeat, with people determined to celebrate the memory of one of the 20th century's towering political figures.