A number of arrests have been made in an international operation to crackdown on "Darknet" websites. More than a dozen countries were involved in the raids including Germany, Britain, and France.
Dutch prosecutors said on Friday that 17 people were arrested in a series of coordinated raids on underground websites selling illegal drugs.
The arrests were made in Germany, the US, and Ireland in one of the biggest crackdowns on the so-called Darknet to date.
The head of the European police agency's cybercrimes division, Troels Oerting, said it had coordinated police operations in more than a dozen countries on Thursday from its headquarters in The Hague, in the Netherlands.
"We will go after drug dealers regardless of whether they operate in the physical or virtual world," said the top Europol official.
The raids included a US operation in which a man was arrested in San Francisco accused of running the Silk Road 2.0 online bazaar, which allegedly sold drugs including Ecstasy, cocaine and LSD.
A total of 414 sites had been seized and closed down in the operation codenamed "Onymous", but Europol declined to say how it had identified vendors and administrators on the Darknet.
The police also recovered $1 million (800,000 euros) in digital currency and $225,000 worth of cash, drugs, gold and silver.
Dark side of the virtual world
The Darknet is a private network where connections are made using non-standard protocols and ports.
Silk Road and similar websites can only be accessed with special browsers that encrypt web traffic for transfer via a network of anonymizing servers. It means users are able to remain invisible online.
Buyers and sellers on Darknet sites trade with digital currencies, including Bitcoin.
"I think there will be more than 55 different markets shut down when the operation is finished", Oerting said. "We didn't get Agora or Evolution [major sites], because there's only so much we can do on one day."
The Darknet marketplace is said to have flourished since the closure of the original Silk Road in October 2013.
In the latest crackdown, the FBI announced it had arrested Blake Benthall on suspicion of running the Silk Road 2.0 site, which was launched weeks after the first Silk Road site was closed.
The 26-year-old faces charges including conspiring to commit narcotics trafficking, conspiring to commit computer hacking, conspiring to traffic in forged documents, and money laundering conspiracy.
Europol chief Oerting gave no further information on arrests in other countries because he said the investigations were ongoing.
"In the next wave we're going to come after people using these sites," he said. "They might hear a knock at the door."
lw/glb (AFP, AP, Reuters)