Police in Milan have said that crimes including weapons and drug trafficking and running of prostitution rings were all co-ordinated through Skype. This made it difficult for authorities to track calls because practice was for police to tap landlines and mobile phones in investigations.According to Eurojust, Skype was refusing to share its secret encryption system with authorities."Skype co-operates with law enforcement where legally and technically possible. Skype remains interested in working with Eurojust despite the fact that they chose not to contact us before issuing this inaccurate report," Brian O’Shaughnessy, head of corporate communications at Skype, said in a statement, as quoted by EUObserver.EUObserver said Bavarian authorities had tried to track a Skype conversation and even had hired an IT firm to do so, but with no success.Skype was developed by Estonian programmers working for a Danish-Swedish business. In 2005, it was sold to E-Bay and now has more than 350 million users around the world.