The US government has claimed responsibility for the largest darknet marketplace takedown in history, shutting down the notorious Alphabay site.
The site went offline on July 5 and its 25-year-old administrator Alexandre Cazes died in the custody of Thai police just over a week ago.
Alphabay was also the marketplace chosen by the vendor who sold Australian Medicare card numbers for around $30 each, as SBS World News independently verified last month.
“This is likely one of the most important criminal investigations of the year – taking down the largest dark net marketplace in history,” Attorney General Jeff Sessions said, according to a statement.
The Medicare scam prompted the Human Services minister Alan Tudge to refer the matter to the Australian Federal Police for investigation.
It is not yet known whether the vendor has opened listings on other dark web markets.
Alphabay was a popular auction site used to buy and sell illegal goods, including drugs and fraud materials, that was well-used in Australia.
It is part of the so-called 'dark web' – an unlisted section of the internet that is not indexed or discoverable through search engines.
It is accessed through the anonymous Tor Network and uses Bitcoin payments to hide the identities of buyers and sellers.
Attorney General Jeff Sessions accused dark web vendors of "pouring fuel on the fire of the national [US] drug epidemic" and warned that "the darknet is not a place to hide”, according to the statement.
US authorities said there were 250,000 listings for illegal drugs and chemicals on the site at the time of the shutdown, along with 100,000 listings for stolen and fraudulent identification documents and access devices, counterfeit goods, malware and other computer hacking tools, firearms and fraudulent services, according to a media release.
Those numbers reveal Alphabay was much larger than the Silk Road dark web marketplace, which was the world’s largest when it was seized by law enforcement in November 2013, with only an approximate 14,000 listings for illicit goods and services.
The US government has also revealed Thai authorities arrested the site’s founder and administrator Alexandre Cazes “on behalf of the United States”.
Mr Cazes died in police custody just over a week ago, according to Thai police. The chief of Thailand's narcotics police told reporters that Cazes was found dead just prior to a scheduled court hearing.
A California indictment said the 25-year-old had amassed a fortune of $23 million, including a small fortune in digital currency.
The indictment said he spent the money on real estate, luxury cars and the pursuit of "economic citizenship" in Liechtenstein, Thailand and Cyprus.
A second dark web marketplace, Hansa, was also shut down.
Dutch cybercrime prosecutor Martijn Egberts told the Associated Press that investigators had taken control of Hansa market and impersonated the administrators for the past month, while many former Alphabay users flocked to the site.
Drug sales continued as usual as investigators logged each transaction and sent shipment details to local police forces in the relevant area.
Over the course of the entire operation, he said that Dutch police were able to scoop up some 10,000 addresses for Hansa buyers outside Holland.
SBS World News has contacted the Department of Human Services and the Australian Federal Police for comment.
-with AAP
