Greeks place illegal bets worth 5bn euros (£4bn; $6.8bn) a year, says the country's "transparency tsar".
General secretary for transparency Giorgos Sourlas proposes a comprehensive crackdown on illegal gambling operations, which are "harming the national economy and acting as a mechanism for laundering ill-gotten gains". Greece is struggling to adjust after a swingeing austerity programme slashed wages and pensions by an average of 40%, while pushing up taxes.
Mr Sourlas told Public Order Minister Vassilis Kikilias that the Hellenic Gaming Commission, which regulates legal gambling, will cooperate with the proposed clean-up: "This makes us optimistic that an end will be put to organized crime rings operating without restraint."
Commission chief Evgenios Giannakopoulos told Kathimerini newspaper that legal betting has seen turnover drop from 8.7bn euros in 2009 to 5.5bn last year - a fall of about 37% - and gross profits slip from 2.5bn euros to 1.5bn. He estimates there are 60,000-100,000 illegal gaming machines in gambling dens, with turnover of 4-5bn euros a year and profits of 1.5bn - all of which bypasses the taxman. "This doesn't include online gambling, which had a turnover of about 1bn euros," Mr Giannakopoulos added.
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