IS accepts Boko Haram's pledge of allegiance

The Islamic State (IS) terrorist group has announced that its leader and self-proclaimed caliph of the Muslim world, Abu Bakr al-Baghdadi, has accepted the pledge of allegiance from the Nigeria-based Boko Haram.

A 28-minute audio message purportedly from an IS spokesman posted online, said that the caliphate, or the Islamic State, has expanded to western Africa and congratulated "our jihadi brothers" there, according to a CNN report on Thursday. The message, however, could not be independently authenticated by CNN.

Boko Haram's leader, Abubakar Shekau, announced in a message last week that the Islamist terrorist group was going to ally with the IS.

His message identified the caliph as Ibrahim ibn Awad ibn Ibrahim al-Awad al-Qurashi, who is better known as Abu Bakr al-Baghdadi, the leader of the IS, according to an earlier report in The Guardian.

Jacob Zenn, a terrorism expert who lives in Nigeria, said that the alliance would make sense for both groups.

"Boko Haram will get legitimacy, which will help its recruiting, funding and logistics as it expands," Zenn said.

"It will also get guidance from ISIS (IS) in media warfare and propaganda. Previously, Boko Haram was sort of an outcast in the global jihadi community. Now it is perhaps IS's biggest affiliate."

He added that following this alliance, the IS would get greater legitimacy as a global caliphate.

The Boko Haram has been a major security threat for Nigeria since 2009 and its tactics have intensified, from battling Nigerian troops to acts disproportionately affecting civilians, such as raids on villages, mass kidnappings, assassinations, market bombings and attacks on churches and unaffiliated mosques.

Much of this violence has taken place in Nigeria, though neighbouring countries, such as Cameroon, Niger and Chad, have also been hit increasingly hard.

The group, whose name in the local dialect translates into "Western education is sin", seeks to impose the Islamic Sharia law in the Nigerian constitution.