Earlier this week Julian Assange, the face of WikiLeaks, voluntarily walked into a London police station to face charges of sexual assault. He is now in custody while his lawyers fight to stop an extradition to Sweden.But while the focus is on the actual charges brought, other law enforcement agencies are building cases against him. The most prominent of these is the government most affected by the WikiLeaks data leaks.AdChoices广告Lawyers representing Assange believe the U.S. government is about to bring charges against him under the Espionage Act. That is key, as it means the U.S. could charge Assange for obtaining information he knew was gathered illegally and a second charge could be brought for not returning any information received of a sensitive nature to the U.S. government.For the moment no such charges have been brought, but with Assange held until at least Tuesday in London, we may see U.S. prosecutors act before the weekend is over.Read more at the TelegraphMatthew’s OpinionWhile Mr. Assange could not be brought up on charges of stealing sensitive information directly, the Espionage Act does seem to allow for serious charges to be brought against anyone who uses such information. With that in mind, and the fact his own lawyers are expecting it, we could see Assange wanted in the U.S. for prosecution next week.The U.S. and the U.K. have a special relationship, so I don’t believe there would be any bid to stop Assange being extradited to the U.S. However, the European Union may have something to say about it due to the existing charges brought over sexual assaults in Sweden.Whatever happens, it doesn’t looks as though Julian Assange is going to be a free man for a while, unless his lawyers manage to negotiate bail terms.