Young rioters have been using their mobiles to egg on one another, boast of their exploits and, in some cases, to organise attacks on the police. Karim, 16, was watching pictures of a battle in another suburb, Sevran. Filmed on a mobile by one of his friends, it showed police using stun guns to disperse a group of youths.

“Look, they keep firing at the youths but nobody’s running away,” Karim said in admiration. “They are really hard in Sevran.” He said that his own gang in Clichy-sous-Bois, where the rioting started, would attempt to outdo the Sevran group. “Everyone wants to burn the most cars,” he said.

Police said that youths in some suburbs were using their mobiles to co-ordinate attacks and lay traps for the police. In one case, in Grigny, a gang was warned of the approach of riot police, which it met with petrol bombs and gunfire. Two officers were seriously injured.

Sofiane, 15, another youth in Clichy-sous-Bois, said: “The mobiles are useful when the police come out, but we just use them to show off to each other. People are sending films of the riots all over the place.”

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