The shocking footage has emerged online showing a woman, who is wearing a black robe, hijab and red jacket, as she is forced to crouch down on her knees.
Surrounding her are several masked and heavily-armed jihadi fighters who crowd around to film the footage on their mobile phones.
Behind her the executioner explains that she has been convicted by an Islamic court for being unfaithful to her husband, as well as running a brothel.
A gunmen, clothed in black and wearing a balaclava, then raises his pistol before shooting her at point black range in the head as chants of Allahu Akbar, ‘God is greatest’ in Arabic ring out from the crowds. The woman was allegedly also convicted of running a brothel.
The jihadists are believed to be from Jabhat al-Nusra Front – a group based in war-torn Syria which has strong allegiances with al-Qaeda.
Yemen’s al-Qaeda branch has already claimed responsibility for last week’s terror attack on French satirical magazine Charlie Hebdo and warned the West of more “tragedies and terror.”
Nasr al-Ansi, a commander of al-Qaeda in the Arabian Peninsula – or AQAP as the branch is known – appeared in an 11-minute video, saying that the massacre at Charlie Hebdo was in “vengeance for the prophet.”