When French police raided a cheap hotel room rented by the Islamic State (Isis) terrorists who had unleashed the Paris massacres on Friday the 13th, they were surprised to find ... used syringes, needles and plastic tubing. There is growing evidence to suggest the gunmen, who killed dozens at the Bataclan venue, fuelled their slaughter with drugs, with some of the survivors of the horror reporting the killers appeared to be in a zombie-like" state. Indeed, the Middle East is awash with Captagon, the trademark name for the synthetic stimulant fenethylline that is almost unheard of in the West. In October, a Saudi prince was arrested at Beirut airport, bound for the Saudi city of Hael, with two tons of Captagon, reportedly worth 190 million ($291m). The drug was largely banned around the world after the World Health Organisation (WHO) listed it as a restricted drug in 1986. It is suspected that he was transporting the drug to sell to militant groups in Syria. In a similar way to cocaine smuggling being used to fund rebel groups in South America, the illicit trade in Captagon is a growing source of income for Syrian groups - potentially including IS - and the drug itself has become a useful tool in sending men and women out to fight, thanks to it causing a euphoric state where some users say they feel invincible.