The announcement from the DOJ coincided with one from the Dutch National Police that appeared on the Hansa Market website, a dark web marketplace many AlphaBay users migrated to after the latter went offline earlier this month.
Sessions also tied the marketplace to several heroin and fentanyl overdoses in the USA, emphasizing AlphaBay's connection to the opioid crisis.
The Atlanta office of the FBI and the U.S. Attorney's Office for the Northern District of Georgia also have identified an AlphaBay staff member living in the United States, an investigation that is still ongoing, according to the Justice Department. These deaths include that of 13-year-old Grant Seaver, who lived in Park City, Utah and died after overdosing on a synthetic opioid one of his classmates bought on AlphaBay, Sessions said.
Law enforcement officials have struggled for years to crack down on these marketplaces, which are hard to locate because their software is distributed across the Tor network, which anonymises users and makes them nearly impossible to track. In recent years, as police have shuttered one market, another has popped up to take its place.
The Dutch police and Europol first gained control of Hansa on June 20, but didn't immediately shut it down.
USA and European police announced on Thursday that they were responsible for the shutdown of two massive darknet marketplaces, AlphaBay and Hansa Market.
"Since the undercover operation to take over Hansa Market by the Dutch police, usernames and passwords of thousands of buyers and sellers of illicit commodities have been identified and are the subject of follow-up investigations by Europol and our partner agencies", Pattison said. The action permitted surveillance of criminal activities on the marketplace before it was shut down in July.
The investigations were a global affair that resulted in the 5 July arrest of an alleged adminstrator of AlphaBay, Canadian Alexandre Cazes, who was arested in Thailand. "We will find and prosecute drug traffickers who set up shop there, and this case is a great example of our commitment to doing exactly that".
AlphaBay's founder, Alexander Cazes, was arrested in Thailand, and US officials successfully negotiated his extradition to the U.S.in early July. According to the Justice Department's press release, Silk Road (which was shut down in 2013) had around 14,000 goods and services listed when it was seized.
Ever since AlphaBay went offline earlier in July, users of the site had discussed potential alternative dark web marketplaces on online forums.
They also seized from Cazes and his wife millions of dollars in currency, luxury cars, and homes in four countries, including a hotel he owned in Thailand. "There are more of these operations to come".
While the marketplace might have been little known outside of the shadowy world of the dark web, officials said it produced real world consequences.