SAN FRANCISCO (CBS SF) — A former U.S. Drug Enforcement Administration agent who admitted stealing more than $500,000 in Bitcoin while investigating the Silk Road black market website was sentenced in federal court in San Francisco Tuesday to six and one-half years in prison.

Carl Force, 46, of Baltimore, was sentenced by U.S. District Judge Richard Seeborg, who also ordered him to pay $340,000 in restitution to one of his victims.

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Force pleaded guilty before Seeborg in July to three counts of extortion, money laundering and obstruction of justice. During the plea, he admitted to an array of corrupt activities while investigating Silk Road and its founder, Ross Ulbricht.

Among other actions, he admitted to pocketing about $190,000 worth of Bitcoin virtual currency he received from Ulbricht while posing in undercover identities. He also admitted to misusing his authority as a DEA agent to seize $337,000 in cash and digital currency from an accountholder in a digital currency company.

Force was one of two federal agents accused of corruption during the Silk Road probe.

The other is former U.S. Secret Service investigator Shaun Bridges, 32, of Laurel, Md. He pleaded guilty to charges of money laundering and obstruction of justice and will be sentenced by Seeborg on Dec. 7.

Silk Road, operated by Ulbricht between 2011 and 2013, was described by the FBI as the “most extensive criminal marketplace on the Internet.” It sold illegal drugs, false identification, computer hacking tools and money laundering services. Buyers purchased items with Bitcoin currency.

Ulbricht was arrested in a San Francisco branch library in 2013.

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He was convicted in federal court in New York this year of seven felonies, including running a continuing criminal enterprise and selling drugs, and was sentenced to life in prison.

Force and Bridges were investigators in a separate probe based in Baltimore, where Ulbricht was charged in federal court with selling cocaine and arranging a murder for hire.

The intended murder victim was a Silk Road employee who had become a government informant. Force became his handler and obtained his password, which Bridges used to steal nearly $20,000 in Bitcoin currency, according to a prosecution sentencing brief.

Ulbricht then believed that the employee was the thief and commissioned Force, who was posing as a foreign drug smuggler, to arrange the murder of the employee, prosecutors said.

Force, Bridges and other agents then staged the supposed waterboarding death of the employee and took photos to be sent to Ulbricht, according to the prosecution brief.

Force also admitted to lying about his actions when he was confronted in May 2014 by federal agents and prosecutors investigating the corruption.

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