ATHENS (Reuters) - A Russian cybercrime suspect told Greek judges on Friday he had  nothing to do  with allegations of masterminding a money-laundering operation using bitcoin. Alexander Vinnik was speaking to a hearing considering his extradition to the United States. He was arrested on a U.S. warrant in a hotel in northern Greece in late July and Russia has since also requested he be sent home on fraud charges.    The U.S. Justice Department says Vinnik facilitated crimes since 2011 including computer hacking, fraud and drug trafficking by laundering at least $4 billion through BTC-e, an exchange used to trade bitcoin and other digital currencies. Vinnik, who was escorted handcuffed through the back door of a Thessaloniki court, denies any wrongdoing. If extradited to the United States, he faces up to 55 years in prison.  He asserts that he has nothing to do with the charges against him,  one of his lawyers, Xanthippi Moisidou, told reporters. The judges are scheduled to announce their verdict on the U.S. request on Oct. 4. A court date for the Russian request has not yet been set.  We hope for, and we expect, a positive result,  said Alexandros Lykourezos, another of Vinnik s lawyers. He said the prosecutor s proposal in favor of extraditing Vinnik was  unsubstantiated.  Greece s justice minister can approve extradition to one country and block the other in the event of competing requests from two or more countries. Vinnik is one of seven Russians arrested or indicted on U.S. cyber crime charges this year and Moscow has sought the extradition of its nationals wanted by the U.S. before.  Yevgeniy Nikulin, an alleged Russian hacker, was arrested in Prague last year and both the United States and Russia want him extradited. Russia s Foreign Ministry had criticized Nikulin s arrest, saying it showed Washington was mounting a global manhunt against Russian citizens. 