A “major online marketplace for hackers” has been shut down, following an international police operation.

RaidForums hosted personal data typically stolen during hacks or data breaches. At the point where it was closed down, the forum was thought to have 10 billion unique records in total, including credit card details, usernames and passwords for UK bank accounts. Armed with such details, even entry-level hackers could create authentic-looking and potentially very successful phishing scams.

Users of the forums would buy or sell these caches of personal data – brazenly doing so on the open web (and not taking to the so-called dark web).

The international operation that finally saw RaidForums taken offline involved police from the UK, US, Germany, Portugal, Romania and Sweden. It not only saw the forum shut down, but also the arrest of 21-year-old Portuguese national Diego Santos Coelho in the UK, as well as another 21-year-old man from Croydon who has since been released pending further investigation.

Coelho – who went by the codename ‘Omnipotent’ – remains in custody pending extradition to the US.

Though lawmakers eventually shut RaidForums down, they didn’t do so immediately. Instead, users were presented with a request to log in at every page they tried to view. Then, after inputting their credentials, they were simply asked to log in again, rather than being redirected. It’s thought this was a further attempt by the law agencies to secure a huge cache of login details from active RaidForums users – which could go some way to shutting down even more hackers in the weeks and months to come.

Launched in 2015, RaidForums became a huge marketplace for cybercriminals, amassing more than 530,000 registered members. Its administrators were based in the UK and were thought to have been laundering membership money through a separate business that otherwise looked legitimate. Following the takedown, the FBI’s Steven M D’Antuono told BBC News: “Cyber-crime transcends borders, which is why the FBI is committed to working with our partners to bring cyber-criminals to justice – no matter where in the world they live or behind what device they try to hide.”