Boko Haram's longtime leader Abubakar Shekau has rejected a move by Islamic State to replace him as the head of Nigeria's Islamist militant group in a purported video that exposes a rift between the two terrorist outfits.
On Wednesday, Arabic-language newspaper al-Nabaa - which is apparently linked to Islamic State - wrote that Boko Haram's new "sheik" was Abu Musab al-Barnawi, according to security think tank SITE Intelligence Group.
Al-Nabaa is an online weekly, and according to its masthead is seven years old - that's before Islamic State emerged and carved a foothold in Iraq and Syria in 2014.
Islamic State's usual propaganda outlets, such as Amaaq News Agency, did not report the change in Boko Haram leadership.
In its latest edition, al-Nabaa has an interview with al-Barnawi, referring to him as the appointed "wali" or ruler of West Africa province but without running a photo of him.
In the interview, he admits military defeats against Boko Haram. "They have usurped some areas from us. We are working to retrieve them," he is quoted as saying in Arabic.
In March 2015, Boko Haram pledged allegiance to Islamic State, which then announced the expansion of its self-declared caliphate to West Africa.
Boko Haram was previously allied with al-Qaeda, of which Islamic State was once an offshoot, but split from that international terrorist network in 2014.
Shekau responded to his apparent dismissal on Thursday with a video message in Hausa and Arabic in which he criticizes "the authorities" - in an apparent reference to Islamic State - for wanting him to be led by an "infidel."
SITE analysts believe this apparent forced change in leadership exposes an ideological rift within Boko Haram.
Boko Haram poses a steady threat to communities in the north-east of Nigeria and has also launched offensives in neighbouring Chad, Niger and Cameroon. The group's goal is to enforce a strict interpretation of Islamic law, known as sharia. Since 2009, at least 14,000 people have died at the hands of the Sunni fundamentalists in Nigeria, Chad, Cameroon and Niger. According to the United Nations, an estimated 2.7 million people in the region have fled their homes due to Boko Haram.