article_snippet: which Boko Haram militants last year declared Gwoza the headquarters of its "caliphate" last Augustwhich Boko Haram militants .
article_snippet: Boko Haram declared Boko Haram own "caliphate" after seizing the area around Gwoza, in Borno state, in August 2014, according to the Chatham House think tank.
article_snippet: Boko Haram has purportedly pledged allegiance to ISIS and says Boko Haram aim is to impose a stricter enforcement of Sharia law across Nigeria, which is split between the majority Muslim north and the mostly Christian south.
article_snippet: Earlier this month, ISIS purportedly said ISIS welcomed Boko Haram after the latter pledged allegiance to ISIS.
article_snippet: In an audio message purportedly from an ISIS spokesman, the rights group announced that the rights group had accepted a pledge of allegiance from Boko Haram.
article_snippet: an audio message purportedly from an ISIS spokesman said that ISIS, which calls itself the Islamic State, had expanded to West Africa and congratulated "our jihadi brothers" there.
article_snippet: an audio message purportedly from an ISIS spokesman followed the posting online of an unauthenticated audio message purportedly from Boko Haram leader, Abubakar Shekau, on March 9 in which the speaker announced that the rights group wanted to join ISIS.
article_snippet: Since 2009, Boko Haram, whose name translates as "Western education is sin," has waged a campaign of terror aimed at instituting a stricter version of Sharia law in Nigeria.
highlights_snippet: Boko Haram declared Gwoza the headquarters of Boko Haram "caliphate" last August .