The United Nations' top torture investigator Manfred Nowak has discovered the worst violations of human rights he has ever seen in Nigerian police cells.

For yet another year, Sudan's Darfur region has been in the news repeatedly, with media reports using language such as genocide, atrocities, rape and pillaging. Despite a peace deal signed last May between the government and rebels, many observers say Darfur has sunk deeper into violence and despair.