An audio tape released by the Islamic State (IS) showed that the terror outfit has accepted a pledge of allegiance from Nigerian militant group Boko Haram.
In the audio message, an IS spokesperson said that the aim of establishing a caliphate has now been expanded to West Africa, reported the BBC.
The authenticity of the tape has not been verified yet.
The news came a week after Boko Haram posted a message pledging allegiance to the IS.
The Nigeria-based militant group started a campaign to impose Islamist rule in northern Nigeria in 2009.
