Boko Haram initially carried out small attacks, but it hit the big time in July 2009, when it launched five days of attacks against churches and political leaders in the northern town of Maiduguri that left 700 people dead.
Boko Haram later organized a prison break in 2010, freeing 700 convicts, some of whom joined Boko Haram’s ranks.
Bombs killed 80 people in the northern city of Jos in Dec. 2010. Bombs exploded over several days in May 2011 following Goodluck Jonathan’s inauguration as president. And an August 2011 bomb blast at UN headquarters in Abuja killed 24.
In June 2011, the group took credit for the suicide car bombing of the Nigerian police headquarters in Abuja in June 2011, saying in a statement that the attack was meant “to prove a point to all those who doubt our capability.”