The footage, posted on jihadist websites yesterday, is said to have been produced by the IS media office in Iraq's Nineveh province, and shows young men testifying to have acted against the jihadists before being shot dead execution style.
The French-speaker wears a beige mask and military fatigues and carries a handgun. Curls of blond hair can be seen below his mask.
The video appears to have been made after the November 13 Paris attacks that killed 130 people and were claimed by IS.
He vows that IS will carry out acts that will make the West forget the 2001 September 11 attacks against the United States that killed nearly 3,000 people, or the Paris carnage.
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He also vows that the West, particularly Spain, will "pay dearly" for having crushed Muslim rule in ancient Andalusia, in southern spain where the Moors ruled from 711 AD to 1492.
He speaks of Cordoba and Toledo and says the ancient land of Andalusia is Muslim and has not been forgotten.
The "execution" appears to take place in the ruins of a building which destroyed in an air strike.