PARIS — Rioters defied a state of emergency that took effect Wednesday, as they looted and burned two superstores, set fire to a newspaper office and paralyzed France's second-largest city's subway system with a firebomb. However, the number of car burnings — a barometer for the unrest — dropped sharply, suggesting the movement lost steam. Overnight Tuesday to Wednesday, youths torched 617 vehicles, down from 1,173 the previous night, national police spokesman Patrick Hamon said. Incidents were reported in 116 towns, down from 226 the night before. President Jacques Chirac announced extraordinary security measures, which began Wednesday and are valid...