One was a stripper, others dealt drugs and several of them visited prostitutes regularly and snorted cocaine. Instead of parading a group of devout Muslim fundamentalists, the trial of 28 people accused of perpetrating the worst Islamic terrorist attack in Europe featured a procession of small-time underworld characters, street-corner drug dealers and petty thieves.

Jamal Zougam, convicted yesterday of planting a bomb on one of the four trains, was reportedly popular with women. One of his friends was quoted as saying: “He was good looking, he didn’t have a beard, he joked around a lot. He’s the kind of guy who would walk around in a Lacoste T-shirt in summer.”

Rafá Zouhier, a former drug dealer turned police informer who was repeatedly reprimanded by the judge for his behaviour in the courtroom, was surprisingly candid about his life. Asked about his work as a stripper in Madrid, he replied: “If I’d been a doctor, a lawyer or a prosecutor, I wouldn’t have known what I knew.”

The party-loving impression left by some of the defendants reflected in part that they were among the lower level figures in the plot left to face trial. The main ringleaders of the Madrid cell blew themselves up when police surrounded their flat three weeks after the attacks. But evidence given in the trial did not portray the ringleaders as particularly pious either.

José Emilio Suárez Trashorras, the schizophrenic Spanish miner who sold the dynamite that was used in the attacks, said that he never considered the head of the cell, Jamal Ahmidan, to be a fundamentalist.

“He enjoyed the Western lifestyle,” Trashorras told the judge. “We went to prostitutes together and took cocaine.”

When police raided the flat of his cousin, Hamid Ahmidan, they found nearly 60kg of hashish and 125,800 Ecstasy pills. The investigating judge found that days before he blew himself up, Ahmidan was closing a significant drug deal in Algeciras, Spain.

“Common criminals became terrorists,” investigating Judge Juan del Olmo found in his report. “There was a transformation of people involved in common crime into terrorist acts.”

Some experts said that drugs were an increasingly common feature of terrorist operations, and are often used to finance cells or attacks.

“It is well established that a part of the dynamite used in the attacks on the trains in Madrid came in exchange for hashish,” Karen Tandy, the Director of the US Drug Enforcement Administration, said this year. She claimed that there is a growing link between drugs and terrorism in many parts of the world.

Other Islamic terror cells have also used men who are not seen as particularly religious. The 9/11 commission found that the Saudi men used as “muscle” in the plane hijackings were mostly unemployed, with only a high school education and little or no connection to religious extremists. Their families did not consider them to be religious zealots, and some were known to drink alcohol.

Unlikely as it may seem, a study by the New York Police Department found recently that these are exactly the type of people who can end up in a radical Islamic terrorist cell. Mitchell Silber and Arvin Bhatt, the authors, examined those accused of the bombings in Madrid, London and elsewhere.

They concluded that cell members often began as unremarkable people from second or third-generation immigrant families, often successful university students with little, if any, criminal history. Most “do not begin as radical or even devout Muslims”, they found. Instead, they were often young men looking for a cause and an identity, which they found in radical Islam.

The judgment into the Madrid train bombings included one detail that described the lives of those convicted for the attack perfectly. The deal to exchange Moroccan hashish for the explosives that ended the lives of 191 people was cut in a McDonald's hamburger outlet at a shopping centre in Madrid.

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