Drug dealing isn’t the reliable career choice it’s cracked up to be, even on the internet. Denizens of The Silk Road, “the eBay of drugs”, are finding that out the hard way. Dealers who lost thousands when Bitcoin crashed last month now find themselves unable to access the site, or their money, for most of the week thanks to a denial of service (or DOS) attack by hackers unknown.

The Silk Road, which bills itself as “The Anonymous Marketplace”, is a smorgasbord of drugs and counterfeit goods. You place an order with a peer-reviewed vendor, pay in Bitcoins and a week later your package arrives (as long as it’s not picked up by Customs or Federal Police).

The site has been in the news lately thanks to an increasing number of prosecutions of users around the world, starting with the jailing of Melbourne man Paul Leslie Howard in February.

The use of Bitcoin as a currency keeps Silk Road users anonymous, as does Tor, a decentralised browsing system that masks users’ identity and location. That decentralisation should have made it impossible for anyone to spam the website but somehow, somebody has found a way.

“It is incredibly discouraging to have everything we’ve worked so hard for taken down by some anonymous and malevolent person,” The Silk Road’s stylishly named founder “Dread Pirate Roberts” said in a statement on Monday. Roberts, prone to rhetorical flourishes, added: “The attacks being used against us MUST be overcome if Silk Road and any anonymous public sites are to have a future.”

Panicked users took to Reddit and The Silk Road’s own forums, which are only working intermittently, to speculate about who is behind the attack and why.

Tom, a user who has spent thousands of dollars buying drugs on The Silk Road, told Crikey there are three theories: “It’s possible that it’s an attack from LE [law enforcement] or it could be an attack by someone who runs another black-market site, trying to draw traffic away from The Silk Road.

“The other theory I’ve heard is that LE set up a competitor website and is now trying to shut down The Silk Road to drive people there like a giant honeypot. But that seems outlandish to me — for it to work, the government would need to be mailing drugs to people.”

Conspiracy theories aside, it’s true The Silk Road now faces increased competition when it comes to selling drugs online. Competitors include sites like Black Market Reloaded, Sheep Marketplace, Russian Anonymous Marketplace and Atlantis.

“Vladimir”, the founder of Atlantis, has been pushing especially hard to recruit vendors and buyers away from The Silk Road. “We believe competition is healthy and believe that Dead [sic] Pirate Roberts is a great leader,” he said in a statement released amid mounting speculation he’s behind the attacks. “We also need to shed the light that Silk Road has had technical issues in the past, even when we weren’t around.”

Whoever’s responsible, it’s hardly surprising they’d play dirty when there’s so much money on the table. The Silk Road alone has a membership that numbers in the tens of thousands. Crikey spoke to vendors that  employ up to five people and turn over thousands of dollars a day.

Dread Pirate Roberts likes to talk about how The Silk Road is a completely free market, unencumbered by regulation. But now he faces the age-old drug dealer’s problem: to whom do you turn if you can’t call the cops?

*Alex McClintock — @axmcc on Twitter — is a freelance writer in Sydney