Iranian anti-narcotics policemen march in formation during a ceremony concluding anti-narcotics manoeuvres in Zahedan, 1,605 kilometers (1,003 miles) southeast of Tehran May 20, 2009. The head of the U.N. crime agency praised Iran during a visit on Wednesday for curbing the flow of smuggled heroin from Afghanistan and helping keep the drug off Western streets. REUTERS/Caren Firouz (IRAN CRIME LAW POLITICS SOCIETY)