The passport may have been bought, stolen, or may be a forgery.
One of the attackers has been named as homegrown terrorist Omar Ismaël Mostefai, 29, from Courcouronnes, Paris. The petty criminal was known to police as a radical and identified by the fingerprint on a severed digit found after he detonated his suicide belt.
Investigators are now investigating claims that he went to Syria last year, and may have spent time training with Isis terrorists.
Survivors have claimed a woman was among the group shooting randomly into the crowd at the Eagles of Death Metal concert before three blew themselves up and a fourth person was shot dead by police before they could detonate their bomb.
At least 129 people died and a further 99 were injured in Paris after eight terrorists, including one as young as 15, attacked the Stade de France, restaurants and the packed Bataclan concert hall armed with AK-47s and grenades and wearing suicide vests.
More than 350 were injured - 99 of whom are in a critical condition - and 30 of the dead have not yet been identified.
It is believed two of the bombers were carrying Syrian passports. At least two others are believed to be French, and several could be Belgian.
- Daily Mail