An anonymous online narcotics marketplace has shut down after an estimated 96,000 Bitcoins - roughly £60m worth - were stolen from the site.
The dark net market 'Sheep Marketplace' rose to prominence after the closure of the illegal Silk Road website by the FBI in October.
Over the weekend the site closed down after what was initially thought to be 5,200 - or £3m worth of Bitcoins were stolen.
A message placed on the homepage of the market blamed a vendor calling themselves "EBOOK101" for exploiting a bug in the system and stealing the virtual currency.
It later became clear that significantly more Bitcoins had been stolen than had been initially thought after a Reddit user tracked down the alleged thief and witnessed him laundering Bitcoins using a method known as “tumbling”.
The Sheep Marketplace emerged as a replacement for the Silk Road after the so-called 'Deep Web' site was closed by the FBI.
By accessing the Silk Road using special software buyers could find all manner of illegal and banned products and services for sale, including drugs and guns. The Sheep Marketplace also offered a range of illegal goods and services.
Over the weekend a message posted on the Sheep Marketplace homepage said: "We are sorry to say, but we were robbed on Saturday 11/21/2013 by vendor EBOOK101."
"This vendor found bug in system and stole 5400 BTC – your money, our provisions, all was stolen. We were trying to resolve this problem, but we were not successful. We are sorry for your problems and inconvenience, all of current BTC will be ditributed to users, who have filled correct BTC emergency adress."
"I would like to thank to all SheepMarketplace moderators by this, who were helping with this problem. I am very sorry for this situation. Thank you all."
The site's operator said that they had since been trying to resolve the situation but had failed and decided to shut down the site.
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