Violence has flared for a fourth night in a suburb of Paris. Groups of youths hurled rocks and bottles and set fire to cars in the north-eastern district of Clichy-sous-Bois, which has a large immigrant population.The rioting began last week after two teenagers believed to be of African origin were electrocuted while fleeing from police. Six police officers were injured and 11 people were arrested last night. The two boys, aged 15 and 17, died after getting into an electricity sub-station. They apparently thought they were being chased by officers although authorities have denied this was the case. Interior Minister Nicolas Sarkozy is to meet the parents of the teenagers. The riots came just days after he launched a new crime offensive, ordering special police units to tackle difficult neighbourhoods around France. But critics say his policies and use of inflammatory language have actually heightened tensions.