Lada Don Adalci na ba da tayin lada da ya kai dalar Amurka miliyan 5 don bayanai kan Ibrahim Ousmane, wanda aka sani da Dandou Cheffou saboda hannunsa a harin 2017 a Tongo Tongo na Nijar. Ibrahim Ousmane kwamandan Daular Islama ta Iraqi da Syria a Yankin Sahara ko ISIS A Babban Yankin Sahara (ISIS in the Greater Sahara –ISIS-GS) ne.
A ranar 4 ga Oktoban 2017, a kusa da ƙauyen Tongo Tongo da ke Nijar, mayaƙa masu alaƙa da ISIS-GS suka kai hari kan mambobin Dakarun Amurka na Musamman da ke horarwa da kuma ba wa sojojin Nijar shawara kan yaƙi da ta’addanci. Harin ya jawo mutuwar sojan Amurka huɗu da na Nijar huɗu. An raunata ƙarin Amurkawa biyu da kuma ‘yan Nijar takwas a harin. A ranar 12 ga watan Janairun 2018, shugaban ISIS-GS Adnan Abu Walid al-Sahrawi ya ɗauki alhakin kai harin.