The Islamic State (Isis/Daesh) terror group has appointed a new leader for its branch in West Africa, the Nigeria-based Islamist outfit Boko Haram. IS announced the appointment of Abu Musab al-Barnawi, former Boko Haram's spokesperson in one of its magazines, the BBC said.

Al-Barnawi replaced Abubakar Shekau, who became the leader of Boko Haram in 2009.

The replacement comes after rumours spread that Shekau had been killed or replaced as the leader has not made a verified video appeareance for the past year.

In March 2016, Boko Haram was believed to have released a video featuring Shekau. However, the unusual poor quality of the footage raised suspicions over its authenticity. Furthermore, the video was only shared on YouTube, rather than on Twitter accounts affiliated with Boko Haram's ally, IS.

Has Nigeria defeated Boko Haram?

Al-Barnawi's appointment came as the Nigerian government and army claimed the fight against Boko Haram was over. However, the claim seemed to be in contradiction with other reports that emerged around the same time.

This is not the first time the Nigerian army and government have claimed that they defeated Boko Haram.

Although Nigeria's President Muhammadu Buhari declared a technical victory over the insurgents in December 2015, Boko Haram has continued to carry out attacks, with security experts warning underlying issues such as disenfranchisement, poverty and strong links with IS continue to pose major threats to stability in the region.

Boko Haram\'s leader Abubakar Shekau
What seems to be Boko Haram's leader Abubakar Shekau in its propaganda video in March 2016 YouTube