Nigeria could be facing a famine worse than any other we've ever seen, the UN said this week. Devastation in Borno state is so complete that millions of people there are threatened with malnutrition. Terrorist group Boko Haram has now been pushed out of Borno state. DW speaks to Ulf Laessing, who was part of the first international news team to see the places Boko Haram had under its control.