Eighteen months ago the world awoke to the kind of news that gives every parent nightmares: almost 300 young girls had been kidnapped from a school in the town of Chibok in Borno State, Nigeria.
Responsibility for the kidnappings was claimed by Boko Haram, an Islamic jihadist and terrorist organization based in northeast Nigeria.
As most of those girls still remain missing, we take a look at the group responsible.
What is Boko Haram?
Boko Haram is an Islamist extremist group responsible for dozens of massacres of civilians and the abduction of more than 500 women and girls in its five-year insurgency in Nigeria.
Boko Haram promotes its own version of Islam which makes it "haram," or forbidden, for Muslims to take part in any political or social activity associated with Western society.
The group's formal name is Jama'atu Ahlis Sunna Lidda'awati wal-Jihad, which in Arabic means "People Committed to the Propagation of the Prophet's Teachings and Jihad." But residents in the northeastern Nigerian city of Maiduguri, where the group originated, dubbed it Boko Haram. Loosely translated from the region's Hausa language, this means "Western education is forbidden."