A bomb blast and explosions that followed killed more than 70 people and injured more than 120 on Monday near Nigeria's capital, Abuja. Early speculation is that the attack was the work of the Boko Haram extremist group. /EPA/Landov hide caption

toggle caption /EPA/Landov

Nigerian President Goodluck Jonathan declares a state of emergency during a live broadcast on state television on Tuesday. Utomi Ekpei/AFP/Getty hide caption

toggle caption Utomi Ekpei/AFP/Getty

NPR's Ofeibea Quist-Arcton on Nigeria's state of emergency

  • <iframe src="https://www.npr.org/player/embed/184201332/184193980" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">

One of the three churches bombed on Sunday in northern Nigeria by Boko Haram, triggering reprisal killings. Olu Ajayi/AP hide caption

toggle caption Olu Ajayi/AP

Onlookers view the wreckage of a car bomb that exploded outside a church near Madalla, Nigeria on Christmas Day, 2011 killing scores of people. Boko Haram claimed responsibility for the attack. Sunday Aghaeze/AP hide caption

toggle caption Sunday Aghaeze/AP