A German police union on Wednesday has warned that riots of the kind that have gripped Britain for the past four nights could happen in Germany. Rainer Wendt, head of the German Police Union (DPolG) said in news remarks that Germany shares the combustible social problems that have driven the massive riots in London and other major cities for the past four nights. "The riots are the result of criminal energy, contempt for the state and the social marginalization of certain groups," he said. This "highly explosive mix" also existed in Germany, particularly in large cities such as Hamburg and Berlin, he said, adding that such flashpoints could arise out of senseless provocation, which can only be contained with great difficulty. Wendt cited the regular May 1 demonstrations in Hamburg and Berlin as examples of how similar unrest could swell up quickly.