A US man has been indicted on charges he was the mastermind behind a website that brokered more than $US1 billion ($A1.15 billion) in transactions for illegal drugs and services.
An indictment unsealed in New York on Tuesday charges Ross William Ulbricht with drug trafficking, computer hacking, money laundering and other counts.
A lawyer for Ulbricht, Joshua Dratel, said his client would plead not guilty on Friday.
"The indictment was expected and does not contain any new factual allegations," Dratel said in a statement.
The 29-year-old Ulbricht was arrested late last year.
Authorities say he operated the Silk Road website under the name "Dread Pirate Roberts".
The website allowed users to anonymously browse nearly 13,000 listings.
Authorities say the categories included "Cannabis," "Psychedelics" and "Stimulants".
Purchases were made using the virtual currency Bitcoin.
