Gwoza, Nigeria A Fulani woman leaves her shelter in one of the town’s camps for internally displaced people. Gwoza was retaken from Boko Haram in March 2015 but the extremists have continued to raid nearby villages. At least 20,000 people have been killed and 2.6 million others displaced since the Islamist group began a rebellion in 2009

Photograph: Stefan Heunis/AFP/Getty Images