SAN FRANCISCO (CBS-SF) — A former U.S. Secret Service agent who stole $820,000 worth of bitcoin from the Silk Road online black market while investigating has been sentenced to five years and 11 months in federal prison.

Shaun Bridges, 33, of Laurel, Md., who investigated Silk Road and its founder, Ross Ulbricht, was sentenced by U.S. District Judge Richard Seeborg on Monday.

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The judge also ordered Bridges to forfeit more than $650,000.

Bridges pleaded guilty before Seeborg in August to one count of laundering the money he stole and one count of obstructing a federal investigation of the theft.

He admitted during the plea to stealing about $350,000 worth of bitcoin from Silk Road accounts in January 2013 and that the funds had become worth $820,000 at the time he transferred the money to an investment account in his name between March and May 2013.

Bridges was one of two federal agents accused and convicted of corruption during the Silk Road probe.

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The other was former U.S. Drug Enforcement Administration Agent Carl Force, 46, of Baltimore. He pleaded guilty to extortion, money laundering and obstruction of justice and was sentenced by Seeborg in October to six and one-half years in prison.

Both Bridges and Force worked in a Baltimore-based task force investigating Ulbricht.

Silk Road, operated by Ulbricht between 2011 and 2013, sold illegal drugs, false identification, computer hacking tools and money laundering services and was described by the FBI as the most extensive criminal marketplace on the Internet at the time. Customers paid for items with bitcoin virtual currency.
The website was shut down after Ulbricht was arrested while using his laptop in a San Francisco branch library in 2013.

In connection with a separate New York-based section of the investigation, Ulbricht was convicted in federal court in New York of seven counts, including running a continuing criminal enterprise and selling drugs, and was sentenced to life in prison.

Bridges gained access to the Silk Road accounts by using the log-in information of a Silk Road customer service representative who had been arrested and was cooperating with authorities.

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