International police have shut down what they called "one of the world's largest" online markets dealing in millions of stolen identities and account details, Europol said on Wednesday.

The global sweep targeting the Genesis Market resulted in 119 arrests, involved 17 countries and was led by the FBI and Dutch police, the EU's policing agency said.

The operation was dubbed "Operation Cookie Monster".

"An unprecedented law enforcement operation involving 17 countries has resulted in the takedown of Genesis Market, one of the most dangerous marketplaces selling stolen account credentials to hackers worldwide," Europol said.

"Genesis Market listed for sale the identities of over two million people when it was shut down," the Hague-based agency said.

Action against criminals took place in countries including Australia, Britain, Canada, the United States and more than 10 countries in Europe.

"Through the combined efforts of all the law enforcement authorities involved, we have severely disrupted the criminal cyber ecosystem by removing one of its key enablers," said Edvardas Sileris, who heads Europol's European Cybercrime Centre, which assisted in the operation.

The EU's judicial agency, Eurojust, which is also based in The Hague said it was a "multi-country effort dubbed Operation Cookie Monster".

"Genesis Market customers were located all over the world and actively purchasing stolen packages of victim data until this takedown," it said.

'Invitation only'

Britain's National Crime Agency said 24 people were arrested in Britain. Another 17 people were arrested in The Netherlands.

Europol said the Genesis Market offered "bots" for sale that had infected victims' devices through malware or other methods.

"Upon purchase of such a bot, criminals would get access to all the data harvested by it such as fingerprints, cookies, saved logins and autofill form data," it said.

The information was collected in real time so buyers would be notified of any change of passwords.

Unlike so-called "dark web" services, Genesis was available on the open web "although obscured from law enforcement behind an invitation-only veil", the agency said.

"Its accessibility and cheap prices greatly lowered the barrier of entry for buyers, making it a popular resource among hackers."

The closure of the Genesis Market comes after a number of cyber crackdowns involving Europol.

In April 2022 it said international investigators had shut down "Raidforums", a massive online forum that sold access to hacked databases stolen from US corporations.

In 2021 it announced the disrupting of the "world's most dangerous" cybercrime malware tool used to break into computer systems, called EMOTET.