Nine cars were torched in Berlin on Thursday in the third consecutive night of arson attacks that have outraged Germans and drawn condemnation from German Chancellor Angela Merkel. While arson attacks on luxury cars in Berlin and Hamburg have been relatively common in recent years, the current spate has attracted increased attention in the wake of Britain's recent outbreak of rioting. Berlin officials say there is no indication of a link, but have few leads on who is behind the nighttime attacks. “We desperately need tips from citizens,” said Rainer Wendt, the head of Germany's police union. Nearly 40 cars have been set on fire in Berlin over the past three days and police are offering a €5,000 ($7,180) reward to anyone who helps them find the perpetrators.