LAGOS, Nigeria (AP) — More than 1,500 people have been killed so far this year in attacks blamed on the Nigerian radical group Boko Haram, whose name means “Western education is forbidden” in the local Hausa language. The terrorist network’s mission is to force an Islamic state on Nigeria, Africa’s most populous nation of some 170 million people divided almost equally between Muslims living mainly in the north and Christians in the south.

Nigeria’s Islamic extremist insurgency grew out of a 2009 riot led by Boko Haram members in Maiduguri, once home to the group’s main mosque, that ended in a security forces’ attack that killed some 700 people. The group’s leader was shot and killed in police custody, fueling dissent that broke into the open in 2010 with the targeted killings of government officials, security agents and religious leaders who spoke out against the sect.