Suspected female suicide bombers kill at least 18 in Nigeria, authorities say

Authorities in Nigeria's northeastern city of Gwoza say at least 18 people have been killed and 30 injured, including 19 seriously, in coordinated attacks by suspected female suicide bombers. Saturday's attacks raise security concerns in a region that has been at the center of an Islamist insurgency. No one has claimed responsibility for the attacks yet, but Gwoza is located in the Borno state, which has been heavily impacted by the insurgency launched in 2009 by Boko Haram, an Islamic extremist group.