Witness

In South Sudan, thousands have been killed, abducted or displaced by Joseph Kony's Lord's Resistance Army. French photojournalist Véronique de Viguerie has been travelling here to cover the Arrow Boys – an unpaid force of farmers.

Though Rio de Janeiro will host the Summer Olympics in 2016, the city remains crippled by a war raging in its narrow favelas between police and powerful drug gangs. Eros Hoagland is one of only a few journalists willing to go into dangerous slums.