Supreme Court prosecutor Giorgos Sanidas arrived in Thessaloniki yesterday to personally investigate an alleged ring of five corrupt judges who are said to have helped a local businessman avoid paying taxes on large amounts of fuel, legal sources said. The five judges allegedly cooperated with lawyers and customs officers to set up a scam involving the bogus export of fuel. Sanidas will question three of the five judges himself, sources said. The other two judges under suspicion have moved to Athens. The justices are being questioned because they allegedly issued rulings in favor of the businessman, who was initially given 15 years in jail after being found guilty of forgery and bribery declaration. However, a few months later he was released on grounds of ill health and his sentence was reduced to 13 years.