Overall, the increased use of crack cocaine, a drug that is produced on the basis of cocaine, is fast-acting and addictive, is a cause for concern in Berlin. Spranger explained that feedback from addiction help centres, addicts and the police point to the spread of crack cocaine use. The phenomenon also exists in other large cities such as Frankfurt am Main, Hamburg, Hanover and Bremen. The reasons are the availability of cocaine, the easy production process, the low price and the high addiction potential.