A Washington state man was charged Tuesday with helping run what investigators called one of the most sophisticated and widely used criminal marketplaces on the Internet.

The Silk Road 2.0 website allowed anonymous users to buy and sell illegal drugs, weapons and other illicit items. It emerged as a copycat site a month after the man accused of running the original Silk Road site was arrested in October 2013.

Following a yearlong investigation, officials on Saturday arrested Brian Richard Farrell, 26, who told federal agents he was a top assistant to the operator of Silk Road 2.0.

Farrell used the moniker "DoctorClu" and was among a small staff of online administrators and forum moderators who helped with the day-to-day operation of the website, according to a criminal complaint filed in U.S. District Court in Seattle.

Farrell was charged with one count of conspiracy to distribute cocaine, heroin and methamphetamine. He made his initial appearance in court Tuesday and U.S. Magistrate Judge Mary Alice Theiler appointed public defender Peter Avenia to represent him.

After the short hearing, Avenia said it was too soon to comment on the case. Assistant U.S. Attorney Nicholas Manheim told the judge the charge carries a mandatory minimum prison term of 10 years and a maximum punishment of life in prison.

Both versions of Silk Road operated on an encrypted network that concealed its operations and locations, according to an affidavit by a U.S. Department of Homeland Security agent. It offered links to various categories of items for sale, including drugs, weapons, fake identification cards, counterfeit merchandise, stolen credit cards and malicious computer software. Users paid for the goods using Bitcoins, a digital currency.

Homeland Security agents tracked Silk Road 2.0 activity to Farrell's Bellevue home in July, according to an affidavit by Special Agent Michael Larson. In the months that followed, agents watched his activities and interviewed a roommate who said Farrell received UPS, FedEx and postal packages daily.

One package was found to contain 107 Xanax pills, Larson said. That led to a search on Jan. 2 that recovered computers, drug paraphernalia, silver bullion bars worth $3,900, and $35,000 in cash, Larson said.

"The arrest of Mr. Farrell is proof that federal law enforcement continues its efforts to root out those who subvert the Internet to set up black markets for illegal goods," Acting U.S. Attorney Annette Hayes said in a statement.

Officials say Farrell was a key assistant to Blake Benthall, the San Francisco man who went by "Defcon" and was charged in November with running Silk Road 2.0. Farrell told authorities he was "Defcon's right-hand man" and "mainly served as Defcon's spokesman," Larson's affidavit said.

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