UK's National Crime Agency moves against Silk Road website British police have arrested four men for alleged links to Silk Road, the online trading site that US authorities shut down last week. The National Crime Agency, which went live on Monday, said that "many more" arrests of users of Silk Road, a semi-secretive site through which people could buy illegal goods and services using the Bitcoin virtual currency, were expected in the coming weeks. Keith Bristow, the NCA director-general, said the arrests demonstrated that the "hidden internet isn't hidden." "It's impossible for criminals to completely erase their digital footprint," he said. No matter how technology-savvy the offender, they will always make mistakes and this brings law enforcement closer to them. The four men, one in his early 50s from Devon and three in their early 20s from Manchester, were arrested hours after the Federal Bureau of Investigation arrested Ross Ulbricht, Silk Road's alleged founder, seized $3.6m of Bitcoins and shut down the site. US authorities described it as "an anonymous Amazon," in reference to the shopping website, and "a sprawling black-market bazaar." Following Mr Ulbricht's arrest, authorities in the US city of Seattle last week arrested Steven Lloyd Sadler, allegedly among the top 1 per cent of sellers on Silk Road and Swedish prosecutors in Malmö have reportedly arrested two people in connection with the site. The FBI believes thousands of people used Silk Road in its two-and-a-half year existence to buy and sell drugs, forged identity papers and other illegal goods, and order assassinations. The total value of the trades exceeded $1.2bn, the FBI believes. The UK was listed as the second most popular country of origin of users after the US, but no verification was offered for this. The NCA said it hoped the Silk Road investigation would help detectives tackle the "deep web," particularly parts of the internet not covered by standard search engines. "These criminal areas of the internet aren't just selling drugs; it's where fraud takes place, where the trafficking of people and goods is discussed, where child abuse images are exchanged and firearms are traded," said Andy Archibald, the head of the NCA's national cyber crime unit. Stopping this element of serious and organised crime will go a long way to protecting the public.