The German police have rolled up a popular marketplace on the dark web, the hidden part of the internet.
The DarkMarket forum had nearly 500,000 users and 2,400 sellers.
Authorities say this is "probably the largest dark web marketplace in the world".
The sellers traded drugs, counterfeit money, stolen credit card information, anonymous SIM cards and malicious software.
In total, more than 140 million euros would have been spent on the platform, in virtual coins such as bitcoin and monero.
The alleged owner of DarkMarket, a 34-year-old Australian, has been arrested near the border between Germany and Denmark.
More than 20 servers in Ukraine and Moldova have been seized.
The German justice wants to use the data on those servers to track down administrators, buyers and sellers.
Marktplaats was found in a search for cyber bunker
The detectives had tracked down the marketplace during the investigation into a so-called cyber bunker.
In an underground old NATO bunker in Germany, more than 400 servers were discovered, which were used for communication via the dark web.
This complex was run by a sixty-year-old Dutchman, who was previously arrested in Germany.
DarkMarket was running on the servers in the bunker for a while.