Boko Haram has set a terrifying new precedent by releasing its first gruesome video of a beheading since it pledged allegiance to ISIS.

The video adopts many of the same style-points as the hundreds of barbaric videos released by ISIS over the last year.

It comes on the same day that MailOnline learned of a Somali terror group's intentions to join ISIS - which would extend its so-called caliphate to east-Africa.

The ten minute-long propaganda video begins with what appears to be an intense firefight against Nigerian soldiers.

The video ends with the senseless murder of a captured African Union soldier. With a look of true horror on his face, the man kneels in front of three masked Boko Haram fanatics - two of whom point AK47s at his head.

The video then cuts to reveal his decapitated body lying motionless on the floor.

Islamic State accepted a pledge of allegiance from Boko Haram, who were responsible for the deaths of over 10,000 in Nigeria in 2014, in March this year.