The first in-depth analysis of AlphaBay, the dark web site shut down by the FBI in July, has revealed the alarming scale of illegal products available for sale in illicit online marketplaces – many of which remain open for business.

Illegal drugs including cannabis, cocaine, heroin, ecstasy and ketamine made up 96 per cent of the estimated $88 million of products on sale on AlphaBay at the time of analysis. The researchers also millions of dollars’ worth of illegal guns, ammunition and other weapons, as well as faked and stolen passports.

There are thought to be 7,000 to 15,000 sites on the dark web, and around a third are marketplaces for illegal trade. Customers access these sites anonymously using TOR or I2P encryption and pay anonymously using cryptocurrency. One well-known illegal marketplace, Dreammarket, has more than 110,000 products currently for sale.

Dr Andres Baravalle and Dr Sin Wee Lee of the University of East London used web crawlers or “spiders” that mimic human browsing behaviour to collect information on AlphaBay for six weeks last summer. Using disposable accounts and anonymised connections, the bots were able to analyse 34,000 adverts without being detected. The results were also filtered to remove fake ads.

Their result point to worrying trends in the trade and consumption of illegal drugs. The UK was the third largest market for the powerful opiod fentanyl, linked to tens of thousands of deaths in the US and sharply rising numbers of deaths in the UK. The Centers for Disease Control and Prevention describes fentanyl as being up to 100 times stronger than morphine.

The UK was the second-largest market on AlphaBay for both buyers and sellers, accounting for 17.9 per cent of adverts for drugs on the site. Large numbers of products were found to have been exported from other countries, however, particularly China and Afghanistan.

The researchers said the marketplaces used regularly updated “security measures and hacker avoidance updates” to stay ahead of law enforcement, but the principal danger was their number and the speed at which they resurface when one is shut down. They plan to focus future research on the role of organised crime in dark web marketplaces, as well as emerging trends in online black markets.

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