BOKO HARAM has used more female suicide-bombers than any other terrorist group in history. Of the 434 bombers the group deployed between April 2011 and June 2017, 244 have been definitely identified as female. More may have been. The Tamil Tigers, the previous holders of the gruesome record, used 44 over a decade, according to a study by Jason Warner and Hilary Matfess for the Combating Terrorism Center at West Point, an American military college. Boko Haram, whose insurgency has killed more than 30,000 in north-east Nigeria and neighbouring countries since 2011 and displaced 2.1m, is also the first group to use a majority of female bombers.