A former U.S. Secret Service special agent appeared in court on charges he stole digital currency during an investigation into an online black market that allowed users to buy and sell drugs and other illegal items.

Shaun W. Bridges of Laurel, Maryland, didn't enter a plea in federal court in San Francisco on Monday. He has been charged with wire fraud and money laundering and was expected to be released after the hearing. Bridges' attorney, Steven Levin, declined to comment.

Carl M. Force of Baltimore, a former special agent with the Drug Enforcement Administration, also has been charged in the case. Force will be in court Monday afternoon.

Force was tasked with establishing communications with a target of the investigation, Ross William Ulbricht, who was convicted on seven drug and conspiracy charges in February.